nping(1) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | TARGET SPECIFICATION | OPTION SPECIFICATION | GENERAL OPERATION | PROBE MODES | TCP CONNECT MODE | TCP MODE | UDP MODE | ICMP MODE | ARP MODE | IPV4 OPTIONS | IPV6 OPTIONS | ETHERNET OPTIONS | PAYLOAD OPTIONS | ECHO MODE | TIMING AND PERFORMANCE OPTIONS | MISCELLANEOUS OPTIONS | OUTPUT OPTIONS | BUGS | AUTHORS | NOTES | COLOPHON

NPING(1)                  Nping Reference Guide                 NPING(1)

NAME         top

       nping - Network packet generation tool / ping utility

SYNOPSIS         top


       nping [Options] {targets}

DESCRIPTION         top

       Nping is an open-source tool for network packet generation,
       response analysis and response time measurement. Nping allows
       users to generate network packets of a wide range of protocols,
       letting them tune virtually any field of the protocol headers.
       While Nping can be used as a simple ping utility to detect active
       hosts, it can also be used as a raw packet generator for network
       stack stress tests, ARP poisoning, Denial of Service attacks,
       route tracing, and other purposes.

       Additionally, Nping offers a special mode of operation called the
       "Echo Mode", that lets users see how the generated probes change
       in transit, revealing the differences between the transmitted
       packets and the packets received at the other end. See section
       "Echo Mode" for details.

       The output from Nping is a list of the packets that are being
       sent and received. The level of detail depends on the options
       used.

       A typical Nping execution is shown in Example 1. The only Nping
       arguments used in this example are -c, to specify the number of
       times to target each host, --tcp to specify TCP Probe Mode, -p
       80,433 to specify the target ports; and then the two target
       hostnames.

       Example 1. A representative Nping execution

           # nping -c 1 --tcp -p 80,433 scanme.nmap.org google.com

           Starting Nping ( https://nmap.org/nping )
           SENT (0.0120s) TCP 96.16.226.135:50091 > 64.13.134.52:80 S ttl=64 id=52072 iplen=40  seq=1077657388 win=1480
           RCVD (0.1810s) TCP 64.13.134.52:80 > 96.16.226.135:50091 SA ttl=53 id=0 iplen=44  seq=4158134847 win=5840 <mss 1460>
           SENT (1.0140s) TCP 96.16.226.135:50091 > 74.125.45.100:80 S ttl=64 id=13932 iplen=40  seq=1077657388 win=1480
           RCVD (1.1370s) TCP 74.125.45.100:80 > 96.16.226.135:50091 SA ttl=52 id=52913 iplen=44  seq=2650443864 win=5720 <mss 1430>
           SENT (2.0140s) TCP 96.16.226.135:50091 > 64.13.134.52:433 S ttl=64 id=8373 iplen=40  seq=1077657388 win=1480
           SENT (3.0140s) TCP 96.16.226.135:50091 > 74.125.45.100:433 S ttl=64 id=23624 iplen=40  seq=1077657388 win=1480

           Statistics for host scanme.nmap.org (64.13.134.52):
            |  Probes Sent: 2 | Rcvd: 1 | Lost: 1  (50.00%)
            |_ Max rtt: 169.720ms | Min rtt: 169.720ms | Avg rtt: 169.720ms
           Statistics for host google.com (74.125.45.100):
            |  Probes Sent: 2 | Rcvd: 1 | Lost: 1  (50.00%)
            |_ Max rtt: 122.686ms | Min rtt: 122.686ms | Avg rtt: 122.686ms
           Raw packets sent: 4 (160B) | Rcvd: 2 (92B) | Lost: 2 (50.00%)
           Tx time: 3.00296s | Tx bytes/s: 53.28 | Tx pkts/s: 1.33
           Rx time: 3.00296s | Rx bytes/s: 30.64 | Rx pkts/s: 0.67
           Nping done: 2 IP addresses pinged in 4.01 seconds

       The newest version of Nping can be obtained with Nmap at
       https://nmap.org . The newest version of this man page is
       available at https://nmap.org/book/nping-man.html .

       -->
         .SH "OPTIONS SUMMARY"

       This options summary is printed when Nping is run with no
       arguments. It helps people remember the most common options, but
       is no substitute for the in-depth documentation in the rest of
       this manual. Some obscure options aren't even included here.

           Nping 0.7.92SVN ( https://nmap.org/nping )
           Usage: nping [Probe mode] [Options] {target specification}

           TARGET SPECIFICATION:
             Targets may be specified as hostnames, IP addresses, networks, etc.
             Ex: scanme.nmap.org, microsoft.com/24, 192.168.0.1; 10.0.*.1-24
           PROBE MODES:
             --tcp-connect                    : Unprivileged TCP connect probe mode.
             --tcp                            : TCP probe mode.
             --udp                            : UDP probe mode.
             --icmp                           : ICMP probe mode.
             --arp                            : ARP/RARP probe mode.
             --tr, --traceroute               : Traceroute mode (can only be used with
                                                TCP/UDP/ICMP modes).
           TCP CONNECT MODE:
              -p, --dest-port <port spec>     : Set destination port(s).
              -g, --source-port <portnumber>  : Try to use a custom source port.
           TCP PROBE MODE:
              -g, --source-port <portnumber>  : Set source port.
              -p, --dest-port <port spec>     : Set destination port(s).
              --seq <seqnumber>               : Set sequence number.
              --flags <flag list>             : Set TCP flags (ACK,PSH,RST,SYN,FIN...)
              --ack <acknumber>               : Set ACK number.
              --win <size>                    : Set window size.
              --badsum                        : Use a random invalid checksum.
           UDP PROBE MODE:
              -g, --source-port <portnumber>  : Set source port.
              -p, --dest-port <port spec>     : Set destination port(s).
              --badsum                        : Use a random invalid checksum.
           ICMP PROBE MODE:
             --icmp-type <type>               : ICMP type.
             --icmp-code <code>               : ICMP code.
             --icmp-id <id>                   : Set identifier.
             --icmp-seq <n>                   : Set sequence number.
             --icmp-redirect-addr <addr>      : Set redirect address.
             --icmp-param-pointer <pnt>       : Set parameter problem pointer.
             --icmp-advert-lifetime <time>    : Set router advertisement lifetime.
             --icmp-advert-entry <IP,pref>    : Add router advertisement entry.
             --icmp-orig-time  <timestamp>    : Set originate timestamp.
             --icmp-recv-time  <timestamp>    : Set receive timestamp.
             --icmp-trans-time <timestamp>    : Set transmit timestamp.
           ARP/RARP PROBE MODE:
             --arp-type <type>                : Type: ARP, ARP-reply, RARP, RARP-reply.
             --arp-sender-mac <mac>           : Set sender MAC address.
             --arp-sender-ip  <addr>          : Set sender IP address.
             --arp-target-mac <mac>           : Set target MAC address.
             --arp-target-ip  <addr>          : Set target IP address.
           IPv4 OPTIONS:
             -S, --source-ip                  : Set source IP address.
             --dest-ip <addr>                 : Set destination IP address (used as an
                                                alternative to {target specification} ).
             --tos <tos>                      : Set type of service field (8bits).
             --id  <id>                       : Set identification field (16 bits).
             --df                             : Set Don't Fragment flag.
             --mf                             : Set More Fragments flag.
             --evil                           : Set Reserved / Evil flag.
             --ttl <hops>                     : Set time to live [0-255].
             --badsum-ip                      : Use a random invalid checksum.
             --ip-options <S|R [route]|L [route]|T|U ...> : Set IP options
             --ip-options <hex string>                    : Set IP options
             --mtu <size>                     : Set MTU. Packets get fragmented if MTU is
                                                small enough.
           IPv6 OPTIONS:
             -6, --IPv6                       : Use IP version 6.
             --dest-ip                        : Set destination IP address (used as an
                                                alternative to {target specification}).
             --hop-limit                      : Set hop limit (same as IPv4 TTL).
             --traffic-class <class> :        : Set traffic class.
             --flow <label>                   : Set flow label.
           ETHERNET OPTIONS:
             --dest-mac <mac>                 : Set destination mac address. (Disables
                                                ARP resolution)
             --source-mac <mac>               : Set source MAC address.
             --ether-type <type>              : Set EtherType value.
           PAYLOAD OPTIONS:
             --data <hex string>              : Include a custom payload.
             --data-string <text>             : Include a custom ASCII text.
             --data-length <len>              : Include len random bytes as payload.
           ECHO CLIENT/SERVER:
             --echo-client <passphrase>       : Run Nping in client mode.
             --echo-server <passphrase>       : Run Nping in server mode.
             --echo-port <port>               : Use custom <port> to listen or connect.
             --no-crypto                      : Disable encryption and authentication.
             --once                           : Stop the server after one connection.
             --safe-payloads                  : Erase application data in echoed packets.
           TIMING AND PERFORMANCE:
             Options which take <time> are in seconds, or append 'ms' (milliseconds),
             's' (seconds), 'm' (minutes), or 'h' (hours) to the value (e.g. 30m, 0.25h).
             --delay <time>                   : Adjust delay between probes.
             --rate  <rate>                   : Send num packets per second.
           MISC:
             -h, --help                       : Display help information.
             -V, --version                    : Display current version number.
             -c, --count <n>                  : Stop after <n> rounds.
             -e, --interface <name>           : Use supplied network interface.
             -H, --hide-sent                  : Do not display sent packets.
             -N, --no-capture                 : Do not try to capture replies.
             --privileged                     : Assume user is fully privileged.
             --unprivileged                   : Assume user lacks raw socket privileges.
             --send-eth                       : Send packets at the raw Ethernet layer.
             --send-ip                        : Send packets using raw IP sockets.
             --bpf-filter <filter spec>       : Specify custom BPF filter.
           OUTPUT:
             -v                               : Increment verbosity level by one.
             -v[level]                        : Set verbosity level. E.g: -v4
             -d                               : Increment debugging level by one.
             -d[level]                        : Set debugging level. E.g: -d3
             -q                               : Decrease verbosity level by one.
             -q[N]                            : Decrease verbosity level N times
             --quiet                          : Set verbosity and debug level to minimum.
             --debug                          : Set verbosity and debug to the max level.
           EXAMPLES:
             nping scanme.nmap.org
             nping --tcp -p 80 --flags rst --ttl 2 192.168.1.1
             nping --icmp --icmp-type time --delay 500ms 192.168.254.254
             nping --echo-server "public" -e wlan0 -vvv
             nping --echo-client "public" echo.nmap.org --tcp -p1-1024 --flags ack

           SEE THE MAN PAGE FOR MANY MORE OPTIONS, DESCRIPTIONS, AND EXAMPLES

TARGET SPECIFICATION         top

       Everything on the Nping command line that isn't an option or an
       option argument is treated as a target host specification. Nping
       uses the same syntax for target specifications that Nmap does.
       The simplest case is a single target given by IP address or
       hostname.

       Nping supports CIDR-style addressing. You can append /numbits to
       an IPv4 address or hostname and Nping will send probes to every
       IP address for which the first numbits are the same as for the
       reference IP or hostname given. For example, 192.168.10.0/24
       would send probes to the 256 hosts between 192.168.10.0 (binary:
       11000000 10101000 00001010 00000000) and 192.168.10.255 (binary:
       11000000 10101000 00001010 11111111), inclusive.
       192.168.10.40/24 would ping exactly the same targets. Given that
       the host scanme.nmap.org is at the IP address 64.13.134.52, the
       specification scanme.nmap.org/16 would send probes to the 65,536
       IP addresses between 64.13.0.0 and 64.13.255.255. The smallest
       allowed value is /0, which targets the whole Internet. The
       largest value is /32, which targets just the named host or IP
       address because all address bits are fixed.

       CIDR notation is short but not always flexible enough. For
       example, you might want to send probes to 192.168.0.0/16 but skip
       any IPs ending with .0 or .255 because they may be used as subnet
       network and broadcast addresses. Nping supports this through
       octet range addressing. Rather than specify a normal IP address,
       you can specify a comma-separated list of numbers or ranges for
       each octet. For example, 192.168.0-255.1-254 will skip all
       addresses in the range that end in .0 or .255, and
       192.168.3-5,7.1 will target the four addresses 192.168.3.1,
       192.168.4.1, 192.168.5.1, and 192.168.7.1. Either side of a range
       may be omitted; the default values are 0 on the left and 255 on
       the right. Using - by itself is the same as 0-255, but remember
       to use 0- in the first octet so the target specification doesn't
       look like a command-line option. Ranges need not be limited to
       the final octets: the specifier 0-.-.13.37 will send probes to
       all IP addresses on the Internet ending in .13.37. This sort of
       broad sampling can be useful for Internet surveys and research.

       IPv6 addresses can only be specified by their fully qualified
       IPv6 address or hostname. CIDR and octet ranges aren't supported
       for IPv6 because they are rarely useful.

       Nping accepts multiple host specifications on the command line,
       and they don't need to be the same type. The command nping
       scanme.nmap.org 192.168.0.0/8 10.0.0,1,3-7.- does what you would
       expect.

OPTION SPECIFICATION         top

       Nping is designed to be very flexible and fit a wide variety of
       needs. As with most command-line tools, its behavior can be
       adjusted using command-line options. These general principles
       apply to option arguments, unless stated otherwise.

       Options that take integer numbers can accept values specified in
       decimal, octal or hexadecimal base. When a number starts with 0x,
       it will be treated as hexadecimal; when it simply starts with 0,
       it will be treated as octal. Otherwise, Nping will assume the
       number has been specified in base 10. Virtually all numbers that
       can be supplied from the command line are unsigned so, as a
       general rule, the minimum value is zero. Users may also specify
       the word random or rand to make Nping generate a random value
       within the expected range.

       IP addresses may be given as IPv4 addresses (e.g.  192.168.1.1),
       IPv6 addresses (e.g.  2001:db8:85a3::8e4c:760:7146), or
       hostnames, which will be resolved using the default DNS server
       configured in the host system.

       Options that take MAC addresses accept the usual colon-separated
       6 hex byte format (e.g.  00:50:56:d4:01:98). Hyphens may also be
       used instead of colons (e.g.  00-50-56-c0-00-08). The special
       word random or rand sets a random address and the word broadcast
       or bcast sets ff:ff:ff:ff:ff:ff.

GENERAL OPERATION         top

       Unlike other ping and packet generation tools, Nping supports
       multiple target host and port specifications. While this provides
       great flexibility, it is not obvious how Nping handles situations
       where there is more than one host and/or more than one port to
       send probes to. This section explains how Nping behaves in these
       cases.

       When multiple target hosts are specified, Nping rotates among
       them in round-robin fashion. This gives slow hosts more time to
       send their responses before another probe is sent to them. Ports
       are also scheduled using round robin. So, unless only one port is
       specified, Nping never sends two probes to the same target host
       and port consecutively.

       The loop around targets is the “inner loop” and the loop around
       ports is the “outer loop”. All targets will be sent a probe for a
       given port before moving on to the next port. Between probes,
       Nping waits a configurable amount of time called the “inter-probe
       delay”, which is controlled by the --delay option. These examples
       show how it works.

               # nping --tcp -c 2 1.1.1.1 -p 100-102

               Starting Nping ( https://nmap.org/nping )
               SENT (0.0210s) TCP 192.168.1.77 > 1.1.1.1:100
               SENT (1.0230s) TCP 192.168.1.77 > 1.1.1.1:101
               SENT (2.0250s) TCP 192.168.1.77 > 1.1.1.1:102
               SENT (3.0280s) TCP 192.168.1.77 > 1.1.1.1:100
               SENT (4.0300s) TCP 192.168.1.77 > 1.1.1.1:101
               SENT (5.0320s) TCP 192.168.1.77 > 1.1.1.1:102

               # nping --tcp -c 2 1.1.1.1 2.2.2.2 3.3.3.3 -p 8080

               Starting Nping ( https://nmap.org/nping )
               SENT (0.0230s) TCP 192.168.0.21 > 1.1.1.1:8080
               SENT (1.0240s) TCP 192.168.0.21 > 2.2.2.2:8080
               SENT (2.0260s) TCP 192.168.0.21 > 3.3.3.3:8080
               SENT (3.0270s) TCP 192.168.0.21 > 1.1.1.1:8080
               SENT (4.0290s) TCP 192.168.0.21 > 2.2.2.2:8080
               SENT (5.0310s) TCP 192.168.0.21 > 3.3.3.3:8080

               # nping --tcp -c 1 --delay 500ms 1.1.1.1 2.2.2.2 3.3.3.3 -p 137-139

               Starting Nping ( https://nmap.org/nping )
               SENT (0.0230s) TCP 192.168.0.21 > 1.1.1.1:137
               SENT (0.5250s) TCP 192.168.0.21 > 2.2.2.2:137
               SENT (1.0250s) TCP 192.168.0.21 > 3.3.3.3:137
               SENT (1.5280s) TCP 192.168.0.21 > 1.1.1.1:138
               SENT (2.0280s) TCP 192.168.0.21 > 2.2.2.2:138
               SENT (2.5310s) TCP 192.168.0.21 > 3.3.3.3:138
               SENT (3.0300s) TCP 192.168.0.21 > 1.1.1.1:139
               SENT (3.5330s) TCP 192.168.0.21 > 2.2.2.2:139
               SENT (4.0330s) TCP 192.168.0.21 > 3.3.3.3:139

PROBE MODES         top

       Nping supports a wide variety of protocols. Although in some
       cases Nping can automatically determine the mode from the options
       used, it is generally a good idea to specify it explicitly.

       --tcp-connect (TCP Connect mode)
           TCP connect mode is the default mode when a user does not
           have raw packet privileges. Instead of writing raw packets as
           most other modes do, Nping asks the underlying operating
           system to establish a connection with the target machine and
           port by issuing the connect system call. This is the same
           high-level system call that web browsers, P2P clients, and
           most other network-enabled applications use to establish a
           connection. It is part of a programming interface known as
           the Berkeley Sockets API. Rather than read raw packet
           responses off the wire, Nping uses this API to obtain status
           information on each connection attempt. For this reason, you
           will not be able to see the contents of the packets that are
           sent or received but only status information about the TCP
           connection establishment taking place.

       --tcp (TCP mode)
           TCP is the mode that lets users create and send any kind of
           TCP packet. TCP packets are sent embedded in IP packets that
           can also be tuned. This mode can be used for many different
           purposes. For example you could try to discover open ports by
           sending TCP SYN messages without completing the three-way
           handshake. This technique is often referred to as half-open
           scanning, because you don't open a full TCP connection. You
           send a SYN packet, as if you are going to open a real
           connection and then wait for a response. A SYN/ACK indicates
           the port is open, while a RST indicates it's closed. If no
           response is received one could assume that some intermediate
           network device is filtering the responses. Another use could
           be to see how a remote TCP/IP stack behaves when it receives
           a non-RFC-compliant packet, like one with both SYN and RST
           flags set. One could also do some evil by creating custom RST
           packets using an spoofed IP address with the intent of
           closing an active TCP connection.

       --udp (UDP mode)
           UDP mode can have two different behaviours. Under normal
           circumstances, it lets users create custom IP/UDP packets.
           However, if Nping is run by a user without raw packet
           privileges and no changes to the default protocol headers are
           requested, then Nping enters the unprivileged UDP mode which
           basically sends UDP packets to the specified target hosts and
           ports using the sendto system call. Note that in this
           unprivileged mode it is not possible to see low-level header
           information of the packets on the wire but only status
           information about the amount of bytes that are being
           transmitted and received. UDP mode can be used to interact
           with any UDP-based server. Examples are DNS servers,
           streaming servers, online gaming servers, and port
           knocking/single-packet authorization daemons.

       --icmp (ICMP mode)
           ICMP mode is the default mode when the user runs Nping with
           raw packet privileges. Any kind of ICMP message can be
           created. The default ICMP type is Echo, i.e., ping. ICMP mode
           can be used for many different purposes, from a simple
           request for a timestamp or a netmask to the transmission of
           fake destination unreachable messages, custom redirects, and
           router advertisements.

       --arp (ARP/RARP mode)
           ARP lets you create and send a few different ARP-related
           packets. These include ARP, RARP, DRARP, and InARP requests
           and replies. This mode can ban be used to perform low-level
           host discovery, and conduct ARP-cache poisoning attacks.

       --traceroute (Traceroute mode)
           Traceroute is not a mode by itself but a complement to TCP,
           UDP, and ICMP modes. When this option is specified Nping will
           set the IP TTL value of the first probe to 1. When the next
           router receives the packet it will drop it due to the
           expiration of the TTL and it will generate an ICMP
           destination unreachable message. The next probe will have a
           TTL of 2 so now the first router will forward the packet
           while the second router will be the one that drops the packet
           and generates the ICMP message. The third probe will have a
           TTL value of 3 and so on. By examining the source addresses
           of all those ICMP Destination Unreachable messages it is
           possible to determine the path that the probes take until
           they reach their final destination.

TCP CONNECT MODE         top

       -p port_spec, --dest-port port_spec (Target ports)
           This option specifies which ports you want to try to connect
           to. It can be a single port, a comma-separated list of ports
           (e.g.  80,443,8080), a range (e.g.  1-1023), and any
           combination of those (e.g.  21-25,80,443,1024-2048). The
           beginning and/or end values of a range may be omitted,
           causing Nping to use 1 and 65535, respectively. So you can
           specify -p- to target ports from 1 through 65535. Using port
           zero is allowed if you specify it explicitly.

       -g portnumber, --source-port portnumber (Spoof source port)
           This option asks Nping to use the specified port as source
           port for the TCP connections. Note that this might not work
           on all systems or may require root privileges. Specified
           value must be an integer in the range [0–65535].

TCP MODE         top

       -p port_spec, --dest-port port_spec (Target ports)
           This option specifies which destination ports you want to
           send probes to. It can be a single port, a comma-separated
           list of ports (e.g.  80,443,8080), a range (e.g.  1-1023),
           and any combination of those (e.g.  21-25,80,443,1024-2048).
           The beginning and/or end values of a range may be omitted,
           causing Nping to use 1 and 65535, respectively. So you can
           specify -p- to target ports from 1 through 65535. Using port
           zero is allowed if you specify it explicitly.

       -g portnumber, --source-port portnumber (Spoof source port)
           This option asks Nping to use the specified port as source
           port for the TCP connections. Note that this might not work
           on all systems or may require root privileges. Specified
           value must be an integer in the range [0–65535].

       --seq seqnumber (Sequence Number)
           Specifies the TCP sequence number. In SYN packets this is the
           initial sequence number (ISN). In a normal transmission this
           corresponds to the sequence number of the first byte of data
           in the segment.  seqnumber must be a number in the range
           [0–4294967295].

       --flags flags (TCP Flags)
           This option specifies which flags should be set in the TCP
           packet.  flags may be specified in three different ways:

            1. As a comma-separated list of flags, e.g.  --flags
               syn,ack,rst

            2. As a list of one-character flag initials, e.g.  --flags
               SAR tells Nping to set flags SYN, ACK, and RST.

            3. As an 8-bit hexadecimal number, where the supplied number
               is the exact value that will be placed in the flags field
               of the TCP header. The number should start with the
               prefix 0x and should be in the range [0x00–0xFF], e.g.
               --flags 0x20 sets the URG flag as 0x20 corresponds to
               binary 00100000 and the URG flag is represented by the
               third bit.

           There are 8 possible flags to set: CWR, ECN, URG, ACK, PSH,
           RST, SYN, and FIN. The special value ALL means to set all
           flags.  NONE means to set no flags. It is important that if
           you don't want any flag to be set, you request it explicitly
           because in some cases the SYN flag may be set by default.
           Here is a brief description of the meaning of each flag:

           CWR (Congestion Window Reduced)
               Set by an ECN-Capable sender when it reduces its
               congestion window (due to a retransmit timeout, a fast
               retransmit or in response to an ECN notification.

           ECN (Explicit Congestion Notification)
               During the three-way handshake it indicates that sender
               is capable of performing explicit congestion
               notification. Normally it means that a packet with the IP
               Congestion Experienced flag set was received during
               normal transmission. See RFC 3168 for more information.

           URG (Urgent)
               Segment is urgent and the urgent pointer field carries
               valid information.

           ACK (Acknowledgement)
               The segment carries an acknowledgement and the value of
               the acknowledgement number field is valid and contains
               the next sequence number that is expected from the
               receiver.

           PSH (Push)
               The data in this segment should be immediately pushed to
               the application layer on arrival.

           RST (Reset)
               There was some problem and the sender wants to abort the
               connection.

           SYN (Synchronize)
               The segment is a request to synchronize sequence numbers
               and establish a connection. The sequence number field
               contains the sender's initial sequence number.

           FIN (Finish)
               The sender wants to close the connection.

       --win size (Window Size)
           Specifies the TCP window size, this is, the number of octets
           the sender of the segment is willing to accept from the
           receiver at one time. This is usually the size of the
           reception buffer that the OS allocates for a given
           connection.  size must be a number in the range [0–65535].

       --badsum (Invalid Checksum)
           Asks Nping to use an invalid TCP checksum for the packets
           sent to target hosts. Since virtually all host IP stacks
           properly drop these packets, any responses received are
           likely coming from a firewall or an IDS that didn't bother to
           verify the checksum. For more details on this technique, see
           https://nmap.org/p60-12.html .

UDP MODE         top

       -p port_spec, --dest-port port_spec (Target ports)
           This option specifies which ports you want UDP datagrams to
           be sent to. It can be a single port, a comma-separated list
           of ports (e.g.  80,443,8080), a range (e.g.  1-1023), and any
           combination of those (e.g.  21-25,80,443,1024-2048). The
           beginning and/or end values of a range may be omitted,
           causing Nping to use 1 and 65535, respectively. So you can
           specify -p- to target ports from 1 through 65535. Using port
           zero is allowed if you specify it explicitly.

       -g portnumber, --source-port portnumber (Spoof source port)
           This option asks Nping to use the specified port as source
           port for the transmitted datagrams. Note that this might not
           work on all systems or may require root privileges. Specified
           value must be an integer in the range [0–65535].

       --badsum (Invalid Checksum)
           Asks Nping to use an invalid UDP checksum for the packets
           sent to target hosts. Since virtually all host IP stacks
           properly drop these packets, any responses received are
           likely coming from a firewall or an IDS that didn't bother to
           verify the checksum. For more details on this technique, see
           https://nmap.org/p60-12.html .

ICMP MODE         top

       --icmp-type type (ICMP type)
           This option specifies which type of ICMP messages should be
           generated.  type can be supplied in two different ways. You
           can use the official type numbers assigned by IANA[1] (e.g.
           --icmp-type 8 for ICMP Echo Request), or you can use any of
           the mnemonics listed in the section called “ICMP Types”.

       --icmp-code code (ICMP code)
           This option specifies which ICMP code should be included in
           the generated ICMP messages.  code can be supplied in two
           different ways. You can use the official code numbers
           assigned by IANA[1] (e.g.  --icmp-code 1 for Fragment
           Reassembly Time Exceeded), or you can use any of the
           mnemonics listed in the section called “ICMP Codes”.

       --icmp-id id (ICMP identifier)
           This option specifies the value of the identifier used in
           some of the ICMP messages. In general it is used to match
           request and reply messages.  id must be a number in the range
           [0–65535].

       --icmp-seq seq (ICMP sequence)
           This option specifies the value of the sequence number field
           used in some ICMP messages. In general it is used to match
           request and reply messages.  id must be a number in the range
           [0–65535].

       --icmp-redirect-addr addr (ICMP Redirect address)
           This option sets the address field in ICMP Redirect messages.
           In other words, it sets the IP address of the router that
           should be used when sending IP datagrams to the original
           destination.  addr can be either an IPv4 address or a
           hostname.

       --icmp-param-pointer pointer (ICMP Parameter Problem pointer)
           This option specifies the pointer that indicates the location
           of the problem in ICMP Parameter Problem messages.  pointer
           should be a number in the range [0–255]. Normally this option
           is only used when ICMP code is set to 0 ("Pointer indicates
           the error").

       --icmp-advert-lifetime ttl (ICMP Router Advertisement Lifetime)
           This option specifies the router advertisement lifetime, this
           is, the number of seconds the information carried in an ICMP
           Router Advertisement can be considered valid for.  ttl must
           be a positive integer in the range [0–65535].

       --icmp-advert-entry addr,pref (ICMP Router Advertisement Entry)
           This option adds a Router Advertisement entry to an ICMP
           Router Advertisement message. The parameter must be two
           values separated by a comma.  addr is the router's IP and can
           be specified either as an IP address in dot-decimal notation
           or as a hostname.  pref is the preference level for the
           specified IP. It must be a number in the range
           [0–4294967295]. An example is --icmp-advert-entry
           192.168.128.1,3.

       --icmp-orig-time timestamp (ICMP Originate Timestamp)
           This option sets the Originate Timestamp in ICMP Timestamp
           messages. The Originate Timestamp is expressed as the number
           of milliseconds since midnight UTC and it corresponds to the
           time the sender last touched the Timestamp message before its
           transmission.  timestamp can be specified as a regular time
           (e.g.  10s, 3h, 1000ms), or the special string now. You can
           add or subtract values from now, for example --icmp-orig-time
           now-2s, --icmp-orig-time now+1h, --icmp-orig-time now+200ms.

       --icmp-recv-time timestamp (ICMP Receive Timestamp)
           This option sets the Receive Timestamp in ICMP Timestamp
           messages. The Receive Timestamp is expressed as the number of
           milliseconds since midnight UTC and it corresponds to the
           time the echoer first touched the Timestamp message on
           receipt.  timestamp is as with --icmp-orig-time.

       --icmp-trans-time timestamp (ICMP Transmit Timestamp)
           This option sets the Transmit Timestamp in ICMP Timestamp
           messages. The Transmit Timestamp is expressed as the number
           of milliseconds since midnight UTC and it corresponds to the
           time the echoer last touched the Timestamp message before its
           transmission.  timestamp is as with --icmp-orig-time.

   ICMP Types
       These identifiers may be used as mnemonics for the ICMP type
       numbers given to the --icmp-type option. In general there are
       three forms of each identifier: the full name (e.g.
       destination-unreachable), the short name (e.g.  dest-unr), or the
       initials (e.g.  du). In ICMP types that request something, the
       word "request" is omitted.

       echo-reply, echo-rep, er
           Echo Reply (type 0). This message is sent in response to an
           Echo Request message.

       destination-unreachable, dest-unr, du
           Destination Unreachable (type 3). This message indicates that
           a datagram could not be delivered to its destination.

       source-quench, sour-que, sq
           Source Quench (type 4). This message is used by a congested
           IP device to tell other device that is sending packets too
           fast and that it should slow down.

       redirect, redi, r
           Redirect (type 5). This message is normally used by routers
           to inform a host that there is a better route to use for
           sending datagrams. See also the --icmp-redirect-addr option.

       echo-request, echo, e
           Echo Request (type 8). This message is used to test the
           connectivity of another device on a network.

       router-advertisement, rout-adv, ra
           Router Advertisement (type 9). This message is used by
           routers to let hosts know of their existence and
           capabilities. See also the --icmp-advert-lifetime option.

       router-solicitation, rout-sol, rs
           Router Solicitation (type 10). This message is used by hosts
           to request Router Advertisement messages from any listening
           routers.

       time-exceeded, time-exc, te
           Time Exceeded (type 11). This message is generated by some
           intermediate device (normally a router) to indicate that a
           datagram has been discarded before reaching its destination
           because the IP TTL expired.

       parameter-problem, member-pro, pp
           Parameter Problem (type 12). This message is used when a
           device finds a problem with a parameter in an IP header and
           it cannot continue processing it. See also the
           --icmp-param-pointer option.

       timestamp, time, tm
           Timestamp Request (type 13). This message is used to request
           a device to send a timestamp value for propagation time
           calculation and clock synchronization. See also the
           --icmp-orig-time, --icmp-recv-time, and --icmp-trans-time.

       timestamp-reply, time-rep, tr
           Timestamp Reply (type 14). This message is sent in response
           to a Timestamp Request message.

       information, info, i
           Information Request (type 15). This message is now obsolete
           but it was originally used to request configuration
           information from another device.

       information-reply, info-rep, ir
           Information Reply (type 16). This message is now obsolete but
           it was originally sent in response to an Information Request
           message to provide configuration information.

       mask-request, mask, m
           Address Mask Request (type 17). This message is used to ask a
           device to send its subnet mask.

       mask-reply, mask-rep, mr
           Address Mask Reply (type 18). This message contains a subnet
           mask and is sent in response to a Address Mask Request
           message.

       traceroute, trace, tc
           Traceroute (type 30). This message is normally sent by an
           intermediate device when it receives an IP datagram with a
           traceroute option. ICMP Traceroute messages are still
           experimental, see RFC 1393 for more information.

   ICMP Codes
       These identifiers may be used as mnemonics for the ICMP code
       numbers given to the --icmp-code option. They are listed by the
       ICMP type they correspond to.

       Destination Unreachable

           network-unreachable, netw-unr, net
               Code 0. Datagram could not be delivered to its
               destination network (probably due to some routing
               problem).

           host-unreachable, host-unr, host
               Code 1. Datagram was delivered to the destination network
               but it was impossible to reach the specified host
               (probably due to some routing problem).

           protocol-unreachable, prot-unr, proto
               Code 2. The protocol specified in the Protocol field of
               the IP datagram is not supported by the host to which the
               datagram was delivered.

           port-unreachable, port-unr, port
               Code 3. The TCP/UDP destination port was invalid.

           needs-fragmentation, need-fra, frag
               Code 4. Datagram had the DF bit set but it was too large
               for the MTU of the next physical network so it had to be
               dropped.

           source-route-failed, sour-rou, routefail
               Code 5. IP datagram had a Source Route option but a
               router couldn't pass it to the next hop.

           network-unknown, netw-unk, net?
               Code 6. Destination network is unknown. This code is
               never used. Instead, Network Unreachable is used.

           host-unknown, host-unk, host?
               Code 7. Specified host is unknown. Usually generated by a
               router local to the destination host to inform of a bad
               address.

           host-isolated, host-iso, isolated
               Code 8. Source Host Isolated. Not used.

           network-prohibited, netw-pro, !net
               Code 9. Communication with destination network is
               administratively prohibited (source device is not allowed
               to send packets to the destination network).

           host-prohibited, host-pro, !host
               Code 10. Communication with destination host is
               administratively prohibited. (The source device is
               allowed to send packets to the destination network but
               not to the destination device.)

           network-tos, unreachable-network-tos, netw-tos, tosnet
               Code 11. Destination network unreachable because it
               cannot provide the type of service specified in the IP
               TOS field.

           host-tos, unreachable-host-tos, toshost
               Code 12. Destination host unreachable because it cannot
               provide the type of service specified in the IP TOS
               field.

           communication-prohibited, comm-pro, !comm
               Code 13. Datagram could not be forwarded due to filtering
               that blocks the message based on its contents.

           host-precedence-violation, precedence-violation, prec-vio,
           violation
               Code 14. Precedence value in the IP TOS field is not
               permitted.

           precedence-cutoff, prec-cut, cutoff
               Code 15. Precedence value in the IP TOS field is lower
               than the minimum allowed for the network.

       Redirect

           redirect-network, redi-net, net
               Code 0. Redirect all future datagrams with the same
               destination network as the original datagram, to the
               router specified in the Address field. The use of this
               code is prohibited by RFC 1812.

           redirect-host, redi-host, host
               Code 1. Redirect all future datagrams with the same
               destination host as the original datagram, to the router
               specified in the Address field.

           redirect-network-tos, redi-ntos, redir-ntos
               Code 2. Redirect all future datagrams with the same
               destination network and IP TOS value as the original
               datagram, to the router specified in the Address field.
               The use of this code is prohibited by RFC 1812.

           redirect-host-tos, redi-htos, redir-htos
               Code 3. Redirect all future datagrams with the same
               destination host and IP TOS value as the original
               datagram, to the router specified in the Address field.

       Router Advertisement

           normal-advertisement, norm-adv, normal, zero, default, def
               Code 0. Normal router advertisement. In Mobile IP:
               Mobility agent can act as a router for IP datagrams not
               related to mobile nodes.

           not-route-common-traffic, not-rou, mobile-ip, !route,
           !commontraffic
               Code 16. Used for Mobile IP. The mobility agent does not
               route common traffic. All foreign agents must forward to
               a default router any datagrams received from a registered
               mobile node

       Time Exceeded

           ttl-exceeded-in-transit, ttl-exc, ttl-transit
               Code 0. IP Time To Live expired during transit.

           fragment-reassembly-time-exceeded, frag-exc, frag-time
               Code 1. Fragment reassembly time has been exceeded.

       Parameter Problem

           pointer-indicates-error, poin-ind, pointer
               Code 0. The pointer field indicates the location of the
               problem. See the --icmp-param-pointer option.

           missing-required-option, miss-option, option-missing
               Code 1. IP datagram was expected to have an option that
               is not present.

           bad-length, bad-len, badlen
               Code 2. The length of the IP datagram is incorrect.

ARP MODE         top

       --arp-type type (ICMP Type)
           This option specifies which type of ARP messages should be
           generated.  type can be supplied in two different ways. You
           can use the official numbers assigned by IANA[2] (e.g.
           --arp-type 1 for ARP Request), or you can use one of the
           mnemonics from the section called “ARP Types”.

       --arp-sender-mac mac (Sender MAC address)
           This option sets the Sender Hardware Address field of the ARP
           header. Although ARP supports many types of link layer
           addresses, currently Nping only supports MAC addresses.  mac
           must be specified using the traditional MAC notation (e.g.
           00:0a:8a:32:f4:ae). You can also use hyphens as separators
           (e.g.  00-0a-8a-32-f4-ae).

       --arp-sender-ip addr (Sender IP address)
           This option sets the Sender IP field of the ARP header.  addr
           can be given as an IPv4 address or a hostname.

       --arp-target-mac mac (target MAC address)
           This option sets the Target Hardware Address field of the ARP
           header.

       --arp-target-ip addr (target ip address)
           This option sets the Target IP field of the ARP header.

   ARP Types
       These identifiers may be used as mnemonics for the ARP type
       numbers given to the --arp-type option.

       arp-request, arp, a
           ARP Request (type 1). ARP requests are used to translate
           network layer addresses (normally IP addresses) to link layer
           addresses (usually MAC addresses). Basically, and ARP request
           is a broadcasted message that asks the host in the same
           network segment that has a given IP address to provide its
           MAC address.

       arp-reply, arp-rep, ar
           ARP Reply (type 2). An ARP reply is a message that a host
           sends in response to an ARP request to provide its link layer
           address.

       rarp-request, rarp, r
           RARP Requests (type 3). RARP requests are used to translate a
           link layer address (normally a MAC address) to a network
           layer address (usually an IP address). Basically a RARP
           request is a broadcasted message sent by a host that wants to
           know his own IP address because it doesn't have any. It was
           the first protocol designed to solve the bootstrapping
           problem. However, RARP is now obsolete and DHCP is used
           instead. For more information about RARP see RFC 903.

       rarp-reply, rarp-rep, rr
           RARP Reply (type 4). A RARP reply is a message sent in
           response to a RARP request to provide an IP address to the
           host that sent the RARP request in the first place.

       drarp-request, drarp, d
           Dynamic RARP Request (type 5). Dynamic RARP is an extension
           to RARP used to obtain or assign a network layer address from
           a fixed link layer address. DRARP was used mainly in Sun
           Microsystems platforms in the late 90's but now it's no
           longer used. See RFC 1931 for more information.

       drarp-reply, drarp-rep, dr
           Dynamic RARP Reply (type 6). A DRARP reply is a message sent
           in response to a RARP request to provide network layer
           address.

       drarp-error, drarp-err, de
           DRARP Error (type 7). DRARP Error messages are usually sent
           in response to DRARP requests to inform of some error. In
           DRARP Error messages, the Target Protocol Address field is
           used to carry an error code (usually in the first byte). The
           error code is intended to tell why no target protocol address
           is being returned. For more information see RFC 1931.

       inarp-request, inarp, i
           Inverse ARP Request (type 8). InARP requests are used to
           translate a link layer address to a network layer address. It
           is similar to RARP request but in this case, the sender of
           the InARP request wants to know the network layer address of
           another node, not its own address. InARP is mainly used in
           Frame Relay and ATM networks. For more information see RFC
           2390.

       inarp-reply, inarp-rep, ir
           Inverse ARP Reply (type 9). InARP reply messages are sent in
           response to InARP requests to provide the network layer
           address associated with the host that has a given link layer
           address.

       arp-nak, an
           ARP NAK (type 10). ARP NAK messages are an extension to the
           ATMARP protocol and they are used to improve the robustness
           of the ATMARP server mechanism. With ARP NAK, a client can
           determine the difference between a catastrophic server
           failure and an ATMARP table lookup failure. See RFC 1577 for
           more information.

IPV4 OPTIONS         top

       -S addr, --source-ip addr (Source IP Address)
           Sets the source IP address. This option lets you specify a
           custom IP address to be used as source IP address in sent
           packets. This allows spoofing the sender of the packets.
           addr can be an IPv4 address or a hostname.

       --dest-ip addr (Destination IP Address)
           Adds a target to Nping's target list. This option is provided
           for consistency but its use is deprecated in favor of plain
           target specifications. See the section called “TARGET
           SPECIFICATION”.

       --tos tos (Type of Service)
           Sets the IP TOS field. The TOS field is used to carry
           information to provide quality of service features. It is
           normally used to support a technique called Differentiated
           Services. See RFC 2474 for more information.  tos must be a
           number in the range [0–255].

       --id id (Identification)
           Sets the IPv4 Identification field. The Identification field
           is a 16-bit value that is common to all fragments belonging
           to a particular message. The value is used by the receiver to
           reassemble the original message from the fragments received.
           id must be a number in the range [0–65535].

       --df (Don't Fragment)
           Sets the Don't Fragment bit in sent packets. When an IP
           datagram has its DF flag set, intermediate devices are not
           allowed to fragment it so if it needs to travel across a
           network with a MTU smaller that datagram length the datagram
           will have to be dropped. Normally an ICMP Destination
           Unreachable message is generated and sent back to the sender.

       --mf (More Fragments)
           Sets the More Fragments bit in sent packets. The MF flag is
           set to indicate the receiver that the current datagram is a
           fragment of some larger datagram. When set to zero it
           indicates that the current datagram is either the last
           fragment in the set or that it is the only fragment.

       --evil (Reserved / Evil)
           Sets the Reserved / Evil bit in sent packets. The Evil flag
           helps firewalls and other network security systems to
           distinguish between datagrams that have malicious intent and
           those that are merely unusual. When set, it indicates that
           the datagram has evil intent, instructing insecure systems to
           succumb. Setting it to zero indicates no evil intent. The
           option is implied if environmental variable SCRIPT_KIDDIE is
           set to a non-zero value.

       --ttl hops (Time To Live)
           Sets the IPv4 Time-To-Live (TTL) field in sent packets to the
           given value. The TTL field specifies how long the datagram is
           allowed to exist on the network. It was originally intended
           to represent a number of seconds but it actually represents
           the number of hops a packet can traverse before being
           dropped. The TTL tries to avoid a situation in which
           undeliverable datagrams keep being forwarded from one router
           to another endlessly.  hops must be a number in the range
           [0–255].

       --badsum-ip (Invalid IP checksum)
           Asks Nping to use an invalid IP checksum for packets sent to
           target hosts. Note that some systems (like most Linux
           kernels), may fix the checksum before placing the packet on
           the wire, so even if Nping shows the incorrect checksum in
           its output, the packets may be transparently corrected by the
           kernel.

       --ip-options R|S [route]|L [route]|T|U ..., --ip-options hex
       string (IP Options)
           The IP protocol offers several options which may be placed in
           packet headers. Unlike the ubiquitous TCP options, IP options
           are rarely seen due to practicality and security concerns. In
           fact, many Internet routers block the most dangerous options
           such as source routing. Yet options can still be useful in
           some cases for determining and manipulating the network route
           to target machines. For example, you may be able to use the
           record route option to determine a path to a target even when
           more traditional traceroute-style approaches fail. Or if your
           packets are being dropped by a certain firewall, you may be
           able to specify a different route with the strict or loose
           source routing options.

           The most powerful way to specify IP options is to simply pass
           in hexadecimal data as the argument to --ip-options. Precede
           each hex byte value with \x. You may repeat certain
           characters by following them with an asterisk and then the
           number of times you wish them to repeat. For example,
           \x01\x07\x04\x00*4 is the same as
           \x01\x07\x04\x00\x00\x00\x00.

           Note that if you specify a number of bytes that is not a
           multiple of four, an incorrect IP header length will be set
           in the IP packet. The reason for this is that the IP header
           length field can only express multiples of four. In those
           cases, the length is computed by dividing the header length
           by 4 and rounding down. This will affect the way the header
           that follows the IP header is interpreted, showing bogus
           information in Nping or in the output of any sniffer.
           Although this kind of situation might be useful for some
           stack stress tests, users would normally want to specify
           explicit padding, so the correct header length is set.

           Nping also offers a shortcut mechanism for specifying
           options. Simply pass the letter R, T, or U to request
           record-route, record-timestamp, or both options together,
           respectively. Loose or strict source routing may be specified
           with an L or S followed by a space and then a space-separated
           list of IP addresses.

           For more information and examples of using IP options with
           Nping, see the mailing list post at
           https://seclists.org/nmap-dev/2006/q3/0052.html .

       --mtu size (Maximum Transmission Unit)
           This option sets a fictional MTU in Nping so IP datagrams
           larger than size are fragmented before transmission.  size
           must be specified in bytes and corresponds to the number of
           octets that can be carried on a single link-layer frame.

IPV6 OPTIONS         top

       -6, --ipv6 (Use IPv6)
           Tells Nping to use IP version 6 instead of the default IPv4.
           It is generally a good idea to specify this option as early
           as possible in the command line so Nping can parse it soon
           and know in advance that the rest of the parameters refer to
           IPv6. The command syntax is the same as usual except that you
           also add the -6 option. Of course, you must use IPv6 syntax
           if you specify an address rather than a hostname. An address
           might look like 3ffe:7501:4819:2000:210:f3ff:fe03:14d0, so
           hostnames are recommended.

           While IPv6 hasn't exactly taken the world by storm, it gets
           significant use in some (usually Asian) countries and most
           modern operating systems support it. To use Nping with IPv6,
           both the source and target of your packets must be configured
           for IPv6. If your ISP (like most of them) does not allocate
           IPv6 addresses to you, free tunnel brokers are widely
           available and work fine with Nping. You can use the free IPv6
           tunnel broker service at http://www.tunnelbroker.net .

           Please note that IPv6 support is still highly experimental
           and many modes and options may not work with it.

       -S addr, --source-ip addr (Source IP Address)
           Sets the source IP address. This option lets you specify a
           custom IP address to be used as source IP address in sent
           packets. This allows spoofing the sender of the packets.
           addr can be an IPv6 address or a hostname.

       --dest-ip addr (Destination IP Address)
           Adds a target to Nping's target list. This option is provided
           for consistency but its use is deprecated in favor of plain
           target specifications. See the section called “TARGET
           SPECIFICATION”.

       --flow label (Flow Label)
           Sets the IPv6 Flow Label. The Flow Label field is 20 bits
           long and is intended to provide certain quality-of-service
           properties for real-time datagram delivery. However, it has
           not been widely adopted, and not all routers or endpoints
           support it. Check RFC 2460 for more information.  label must
           be an integer in the range [0–1048575].

       --traffic-class class (Traffic Class)
           Sets the IPv6 Traffic Class. This field is similar to the TOS
           field in IPv4, and is intended to provide the Differentiated
           Services method, enabling scalable service discrimination in
           the Internet without the need for per-flow state and
           signaling at every hop. Check RFC 2474 for more information.
           class must be an integer in the range [0–255].

       --hop-limit hops (Hop Limit)

           Sets the IPv6 Hop Limit field in sent packets to the given
           value. The Hop Limit field specifies how long the datagram is
           allowed to exist on the network. It represents the number of
           hops a packet can traverse before being dropped. As with the
           TTL in IPv4, IPv6 Hop Limit tries to avoid a situation in
           which undeliverable datagrams keep being forwarded from one
           router to another endlessly.  hops must be a number in the
           range [0–255].

ETHERNET OPTIONS         top

       In most cases Nping sends packets at the raw IP level. This means
       that Nping creates its own IP packets and transmits them through
       a raw socket. However, in some cases it may be necessary to send
       packets at the raw Ethernet level. This happens, for example,
       when Nping is run under Windows (as Microsoft has disabled raw
       socket support since Windows XP SP2), or when Nping is asked to
       send ARP packets. Since in some cases it is necessary to
       construct ethernet frames, Nping offers some options to
       manipulate the different fields.

       --dest-mac mac (Ethernet Destination MAC Address)
           This option sets the destination MAC address that should be
           set in outgoing Ethernet frames. This is useful in case Nping
           can't determine the next hop's MAC address or when you want
           to route probes through a router other than the configured
           default gateway. The MAC address should have the usual format
           of six colon-separated bytes, e.g.  00:50:56:d4:01:98.
           Alternatively, hyphens may be used instead of colons. Use the
           word random or rand to generate a random address, and
           broadcast or bcast to use ff:ff:ff:ff:ff:ff. If you set up a
           bogus destination MAC address your probes may not reach the
           intended targets.

       --source-mac mac (Ethernet Source MAC Address)
           This option sets the source MAC address that should be set in
           outgoing Ethernet frames. This is useful in case Nping can't
           determine your network interface MAC address or when you want
           to inject traffic into the network while hiding your network
           card's real address. The syntax is the same as for
           --dest-mac. If you set up a bogus source MAC address you may
           not receive probe replies.

       --ether-type type (Ethertype)
           This option sets the Ethertype field of the ethernet frame.
           The Ethertype is used to indicate which protocol is
           encapsulated in the payload.  type can be supplied in two
           different ways. You can use the official numbers listed by
           the IEEE[3] (e.g.  --ether-type 0x0800 for IP version 4), or
           one of the mnemonics from the section called “Ethernet
           Types”.

   Ethernet Types
       These identifiers may be used as mnemonics for the Ethertype
       numbers given to the --arp-type option.

       ipv4, ip, 4
           Internet Protocol version 4 (type 0x0800).

       ipv6, 6
           Internet Protocol version 6 (type 0x86DD).

       arp
           Address Resolution Protocol (type 0x0806).

       rarp
           Reverse Address Resolution Protocol (type 0x8035).

       frame-relay, frelay, fr
           Frame Relay (type 0x0808).

       ppp
           Point-to-Point Protocol (type 0x880B).

       gsmp
           General Switch Management Protocol (type 0x880C).

       mpls
           Multiprotocol Label Switching (type 0x8847).

       mps-ual, mps
           Multiprotocol Label Switching with Upstream-assigned Label
           (type 0x8848).

       mcap
           Multicast Channel Allocation Protocol (type 0x8861).

       pppoe-discovery, pppoe-d
           PPP over Ethernet Discovery Stage (type 0x8863).

       pppoe-session, pppoe-s
           PPP over Ethernet Session Stage (type 0x8864).

       ctag
           Customer VLAN Tag Type (type 0x8100).

       epon
           Ethernet Passive Optical Network (type 0x8808).

       pbnac
           Port-based network access control (type 0x888E).

       stag
           Service VLAN tag identifier (type 0x88A8).

       ethexp1
           Local Experimental Ethertype 1 (type 0x88B5).

       ethexp2
           Local Experimental Ethertype 2 (type 0x88B6).

       ethoui
           OUI Extended Ethertype (type 0x88B7).

       preauth
           Pre-Authentication (type 0x88C7).

       lldp
           Link Layer Discovery Protocol (type 0x88CC).

       mac-security, mac-sec, macsec
           Media Access Control Security (type 0x88E5).

       mvrp
           Multiple VLAN Registration Protocol (type 0x88F5).

       mmrp
           Multiple Multicast Registration Protocol (type 0x88F6).

       frrr
           Fast Roaming Remote Request (type 0x890D).

PAYLOAD OPTIONS         top

       --data hex string (Append custom binary data to sent packets)
           This option lets you include binary data as payload in sent
           packets.  hex string may be specified in any of the following
           formats: 0xAABBCCDDEEFF..., AABBCCDDEEFF...  or
           \xAA\xBB\xCC\xDD\xEE\xFF.... Examples of use are --data
           0xdeadbeef and --data \xCA\xFE\x09. Note that if you specify
           a number like 0x00ff no byte-order conversion is performed.
           Make sure you specify the information in the byte order
           expected by the receiver.

       --data-string string (Append custom string to sent packets)
           This option lets you include a regular string as payload in
           sent packets.  string can contain any string. However, note
           that some characters may depend on your system's locale and
           the receiver may not see the same information. Also, make
           sure you enclose the string in double quotes and escape any
           special characters from the shell. Example: --data-string
           "Jimmy Jazz...".

       --data-length len (Append random data to sent packets)
           This option lets you include len random bytes of data as
           payload in sent packets.  len must be an integer in the range
           [0–65400]. However, values higher than 1400 are not
           recommended because it may not be possible to transmit
           packets due to network MTU limitations.

ECHO MODE         top

       The "Echo Mode" is a novel technique implemented by Nping which
       lets users see how network packets change in transit, from the
       host where they originated to the target machine. Basically, the
       Echo mode turns Nping into two different pieces: the Echo server
       and the Echo client. The Echo server is a network service that
       has the ability to capture packets from the network and send a
       copy ("echo them") to the originating client through a side TCP
       channel. The Echo client is the part that generates such network
       packets, transmits them to the server, and receives their echoed
       version through a side TCP channel that it has previously
       established with the Echo server.

       This scheme lets the client see the differences between the
       packets that it sends and what is actually received by the
       server. By having the server send back copies of the received
       packets through the side channel, things like NAT devices become
       immediately apparent to the client because it notices the changes
       in the source IP address (and maybe even source port). Other
       devices like those that perform traffic shaping, changing TCP
       window sizes or adding TCP options transparently between hosts,
       turn up too.

       The Echo mode is also useful for troubleshooting routing and
       firewall issues. Among other things, it can be used to determine
       if the traffic generated by the Nping client is being dropped in
       transit and never gets to its destination or if the responses are
       the ones that don't get back to it.

       Internally, client and server communicate over an encrypted and
       authenticated channel, using the Nping Echo Protocol (NEP), whose
       technical specification can be found in
       https://nmap.org/svn/nping/docs/EchoProtoRFC.txt 

       The following paragraphs describe the different options available
       in Nping's Echo mode.

       --ec passphrase, --echo-client passphrase (Run Echo client)
           This option tells Nping to run as an Echo client.  passphrase
           is a sequence of ASCII characters that is used used to
           generate the cryptographic keys needed for encryption and
           authentication in a given session. The passphrase should be a
           secret that is also known by the server, and it may contain
           any number of printable ASCII characters. Passphrases that
           contain whitespace or special characters must be enclosed in
           double quotes.

           When running Nping as an Echo client, most options from the
           regular raw probe modes apply. The client may be configured
           to send specific probes using flags like --tcp, --icmp or
           --udp. Protocol header fields may be manipulated normally
           using the appropriate options (e.g.  --ttl, --seq,
           --icmp-type, etc.). The only exceptions are ARP-related
           flags, which are not supported in Echo mode, as protocols
           like ARP are closely related to the data link layer and its
           probes can't pass through different network segments.

       --es passphrase, --echo-server passphrase (Run Echo server)
           This option tells Nping to run as an Echo server.  passphrase
           is a sequence of ASCII characters that is used used to
           generate the cryptographic keys needed for encryption and
           authentication in a given session. The passphrase should be a
           secret that is also known by the clients, and it may contain
           any number of printable ASCII characters. Passphrases that
           contain whitespace or special characters must be enclosed in
           double quotes. Note that although it is not recommended, it
           is possible to use empty passphrases, supplying --echo-server
           "". However, if what you want is to set up an open Echo
           server, it is better to use option --no-crypto. See below for
           details.

       --ep port, --echo-port port (Set Echo TCP port number)
           This option asks Nping to use the specified TCP port number
           for the Echo side channel connection. If this option is used
           with --echo-server, it specifies the port on which the server
           listens for connections. If it is used with --echo-client, it
           specifies the port to connect to on the remote host. By
           default, port number 9929 is used.

       --nc, --no-crypto (Disable encryption and authentication)
           This option asks Nping not to use any cryptographic
           operations during an Echo session. In practical terms, this
           means that the Echo side channel session data will be
           transmitted in the clear, and no authentication will be
           performed by the server or client during the session
           establishment phase. When --no-crypto is used, the passphrase
           supplied with --echo-server or --echo-client is ignored.

           This option must be specified if Nping was compiled without
           openSSL support. Note that, for technical reasons, a
           passphrase still needs to be supplied after the --echo-client
           or --echo-server flags, even though it will be ignored.

           The --no-crypto flag might be useful when setting up a public
           Echo server, because it allows users to connect to the Echo
           server without the need for any passphrase or shared secret.
           However, it is strongly recommended to not use --no-crypto
           unless absolutely necessary. Public Echo servers should be
           configured to use the passphrase "public" or the empty
           passphrase (--echo-server "") as the use of cryptography does
           not only provide confidentiality and authentication but also
           message integrity.

       --once (Serve one client and quit)
           This option asks the Echo server to quit after serving one
           client. This is useful when only a single Echo session wants
           to be established as it eliminates the need to access the
           remote host to shutdown the server.

       --safe-payloads (Zero application data before echoing a packet)
           This option asks the Echo server to erase any application
           layer data found in client packets before echoing them. When
           the option is enabled, the Echo server parses the packets
           received from Echo clients and tries to determine if they
           contain data beyond the transport layer. If such data is
           found, it is overwritten with zeroes before transmitting the
           packets to the appropriate Echo client.

           Echo servers can handle multiple simultaneous clients running
           multiple echo sessions in parallel. In order to determine
           which packet needs to be echoed to which client and through
           which session, the Echo server uses an heuristic algorithm.
           Although we have taken every security measure that we could
           think of to prevent that a client receives an echoed packet
           that it did not generate, there is always a risk that our
           algorithm makes a mistake and delivers a packet to the wrong
           client. The --safe-payloads option is useful for public echo
           servers or critical deployments where that kind of mistake
           cannot be afforded.

       The following examples illustrate how Nping's Echo mode can be
       used to discover intermediate devices.

       Example 2. Discovering NAT devices

               # nping --echo-client "public" echo.nmap.org --udp

               Starting Nping ( https://nmap.org/nping )
               SENT (1.0970s) UDP 10.1.20.128:53 > 178.79.165.17:40125 ttl=64 id=32523 iplen=28
               CAPT (1.1270s) UDP 80.38.10.21:45657 > 178.79.165.17:40125 ttl=54 id=32523 iplen=28
               RCVD (1.1570s) ICMP 178.79.165.17 > 10.1.20.128 Port unreachable (type=3/code=3) ttl=49 id=16619 iplen=56
               [...]
               SENT (5.1020s) UDP 10.1.20.128:53 > 178.79.165.17:40125 ttl=64 id=32523 iplen=28
               CAPT (5.1335s) UDP 80.38.10.21:45657 > 178.79.165.17:40125 ttl=54 id=32523 iplen=28
               RCVD (5.1600s) ICMP 178.79.165.17 > 10.1.20.128 Port unreachable (type=3/code=3) ttl=49 id=16623 iplen=56

               Max rtt: 60.628ms | Min rtt: 58.378ms | Avg rtt: 59.389ms
               Raw packets sent: 5 (140B) | Rcvd: 5 (280B) | Lost: 0 (0.00%)| Echoed: 5 (140B)
               Tx time: 4.00459s | Tx bytes/s: 34.96 | Tx pkts/s: 1.25
               Rx time: 5.00629s | Rx bytes/s: 55.93 | Rx pkts/s: 1.00
               Nping done: 1 IP address pinged in 6.18 seconds

       The output clearly shows the presence of a NAT device in the
       client's local network. Note how the captured packet (CAPT)
       differs from the SENT packet: the source address for the original
       packets is in the reserved 10.0.0.0/8 range, while the address
       seen by the server is 80.38.10.21, the Internet side address of
       the NAT device. The source port was also modified by the device.
       The line starting with RCVD corresponds to the responses
       generated by the TCP/IP stack of the machine where the Echo
       server is run.

       Example 3. Discovering a transparent proxy

               # nping --echo-client "public" echo.nmap.org --tcp -p80

               Starting Nping ( https://nmap.org/nping )
               SENT (1.2160s) TCP 10.0.1.77:41659 > 178.79.165.17:80 S ttl=64 id=3317 iplen=40  seq=567704200 win=1480
               RCVD (1.2180s) TCP 178.79.165.17:80 > 10.0.1.77:41659 SA ttl=128 id=13177 iplen=44  seq=3647106954 win=16384 <mss 1460>
               SENT (2.2150s) TCP 10.0.1.77:41659 > 178.79.165.17:80 S ttl=64 id=3317 iplen=40  seq=567704200 win=1480
               SENT (3.2180s) TCP 10.0.1.77:41659 > 178.79.165.17:80 S ttl=64 id=3317 iplen=40  seq=567704200 win=1480
               SENT (4.2190s) TCP 10.0.1.77:41659 > 178.79.165.17:80 S ttl=64 id=3317 iplen=40  seq=567704200 win=1480
               SENT (5.2200s) TCP 10.0.1.77:41659 > 178.79.165.17:80 S ttl=64 id=3317 iplen=40  seq=567704200 win=1480

               Max rtt: 2.062ms | Min rtt: 2.062ms | Avg rtt: 2.062ms
               Raw packets sent: 5 (200B) | Rcvd: 1 (46B) | Lost: 4 (80.00%)| Echoed: 0 (0B)
               Tx time: 4.00504s | Tx bytes/s: 49.94 | Tx pkts/s: 1.25
               Rx time: 5.00618s | Rx bytes/s: 9.19 | Rx pkts/s: 0.20
               Nping done: 1 IP address pinged in 6.39 seconds

       In this example, the output is a bit more tricky. The absence of
       error messages shows that the Echo client has successfully
       established an Echo session with the server. However, no CAPT
       packets can be seen in the output. This means that none of the
       transmitted packets reached the server. Interestingly, a TCP
       SYN-ACK packet was received in response to the first TCP-SYN
       packet (and also, it is known that the target host does not have
       port 80 open). This behavior reveals the presence of a
       transparent web proxy cache server (which in this case is an old
       MS ISA server).

TIMING AND PERFORMANCE OPTIONS         top

       --delay time (Delay between probes)
           This option lets you control for how long will Nping wait
           before sending the next probe. Like in many other ping tools,
           the default delay is one second.  time must be a positive
           integer or floating point number. By default it is specified
           in seconds, however you can give an explicit unit by
           appending ms for milliseconds, s for seconds, m for minutes,
           or h for hours (e.g.  2.5s, 45m, 2h).

       --rate rate (Send probes at a given rate)
           This option specifies the number of probes that Nping should
           send per second. This option and --delay are inverses; --rate
           20 is the same as --delay 0.05. If both options are used,
           only the last one in the parameter list counts.

MISCELLANEOUS OPTIONS         top

       -h, --help (Display help)
           Displays help information and exits.

       -V, --version (Display version)
           Displays the program's version number and quits.

       -c rounds, --count rounds (Stop after a given number of rounds)
           This option lets you specify the number of times that Nping
           should loop over target hosts (and in some cases target
           ports). Nping calls these “rounds”. In a basic execution with
           only one target (and only one target port in TCP/UDP modes),
           the number of rounds matches the number of probes sent to the
           target host. However, in more complex executions where Nping
           is run against multiple targets and multiple ports, the
           number of rounds is the number of times that Nping sends a
           complete set of probes that covers all target IPs and all
           target ports. For example, if Nping is asked to send TCP SYN
           packets to hosts 192.168.1.0-255 and ports 80 and 433, then
           256 × 2 = 512 packets are sent in one round. So if you
           specify -c 100, Nping will loop over the different target
           hosts and ports 100 times, sending a total of 256 × 2 ×
           100 = 51200 packets. By default Nping runs for 5 rounds. If a
           value of 0 is specified, Nping will run continuously.

       -e name, --interface name (Set the network interface to be used)
           This option tells Nping what interface should be used to send
           and receive packets. Nping should be able to detect this
           automatically, but it will tell you if it cannot.  name must
           be the name of an existing network interface with an assigned
           IP address.

       --privileged (Assume that the user is fully privileged)
           Tells Nping to simply assume that it is privileged enough to
           perform raw socket sends, packet sniffing, and similar
           operations that usually require special privileges. By
           default Nping quits if such operations are requested by a
           user that has no root or administrator privileges. This
           option may be useful on Linux, BSD or similar systems that
           can be configured to allow unprivileged users to perform
           raw-packet transmissions. The NPING_PRIVILEGED environment
           variable may be set as an alternative to using --privileged.

       --unprivileged (Assume that the user lacks raw socket privileges)
           This option is the opposite of --privileged. It tells Nping
           to treat the user as lacking network raw socket and sniffing
           privileges. This is useful for testing, debugging, or when
           the raw network functionality of your operating system is
           somehow broken. The NPING_UNPRIVILEGED environment variable
           may be set as an alternative to using --unprivileged.

       --send-eth (Use raw ethernet sending)
           Asks Nping to send packets at the raw ethernet (data link)
           layer rather than the higher IP (network) layer. By default,
           Nping chooses the one which is generally best for the
           platform it is running on. Raw sockets (IP layer) are
           generally most efficient for Unix machines, while ethernet
           frames are required for Windows operation since Microsoft
           disabled raw socket support. Nping still uses raw IP packets
           despite this option when there is no other choice (such as
           non-ethernet connections).

       --send-ip (Send at raw IP level)
           Asks Nping to send packets via raw IP sockets rather than
           sending lower level ethernet frames. It is the complement to
           the --send-eth option.

       --bpf-filter filter spec --filter filter spec (Set custom BPF
       filter)
           This option lets you use a custom BPF filter. By default
           Nping chooses a filter that is intended to capture most
           common responses to the particular probes that are sent. For
           example, when sending TCP packets, the filter is set to
           capture packets whose destination port matches the probe's
           source port or ICMP error messages that may be generated by
           the target or any intermediate device as a result of the
           probe. If for some reason you expect strange packets in
           response to sent probes or you just want to sniff a
           particular kind of traffic, you can specify a custom filter
           using the BPF syntax used by tools like tcpdump.  See the
           documentation at http://www.tcpdump.org/ for more
           information.

       -H, --hide-sent (Do not display sent packets)
           This option tells Nping not to print information about sent
           packets. This can be useful when using very short inter-probe
           delays (i.e., when flooding), because printing information to
           the standard output has a computational cost and disabling it
           can probably speed things up a bit. Also, it may be useful
           when using Nping to detect active hosts or open ports (e.g.
           sending probes to all TCP ports in a /24 subnet). In that
           case, users may not want to see thousands of sent probes but
           just the replies generated by active hosts.

       -N, --no-capture (Do not attempt to capture replies)
           This option tells Nping to skip packet capture. This means
           that packets in response to sent probes will not be processed
           or displayed. This can be useful when doing flooding and
           network stack stress tests. Note that when this option is
           specified, most of the statistics shown at the end of the
           execution will be useless. This option does not work with TCP
           Connect mode.

OUTPUT OPTIONS         top

       -v[level], --verbose [level] (Increase or set verbosity level)
           Increases the verbosity level, causing Nping to print more
           information during its execution. There are 9 levels of
           verbosity (-4 to 4). Every instance of -v increments the
           verbosity level by one (from its default value, level 0).
           Every instance of option -q decrements the verbosity level by
           one. Alternatively you can specify the level directly, as in
           -v3 or -v-1. These are the available levels:

           Level -4
               No output at all. In some circumstances you may not want
               Nping to produce any output (like when one of your work
               mates is watching over your shoulder). In that case level
               -4 can be useful because although you won't see any
               response packets, probes will still be sent.

           Level -3
               Like level -4 but displays fatal error messages so you
               can actually see if Nping is running or it failed due to
               some error.

           Level -2
               Like level -3 but also displays warnings and recoverable
               errors.

           Level -1
               Displays traditional run-time information (version, start
               time, statistics, etc.) but does not display sent or
               received packets.

           Level 0
               This is the default verbosity level. It behaves like
               level -1 but also displays sent and received packets and
               some other important information.

           Level 1
               Like level 0 but it displays detailed information about
               timing, flags, protocol details, etc.

           Level 2
               Like level 1 but displays very detailed information about
               sent and received packets and other interesting
               information.

           Level 3
               Like level 2 but also displays the raw hexadecimal dump
               of sent and received packets.

           Level 4 and higher
               Same as level 3.

       -q[level], --reduce-verbosity [level] (Decrease verbosity level)
           Decreases the verbosity level, causing Nping to print less
           information during its execution.

       -d[level] (Increase or set debugging level)
           When even verbose mode doesn't provide sufficient data for
           you, debugging is available to flood you with much more! As
           with the -v, debugging is enabled with a command-line flag -d
           and the debug level can be increased by specifying it
           multiple times. There are 7 debugging levels (0 to 6). Every
           instance of -d increments debugging level by one. Provide an
           argument to -d to set the level directly; for example -d4.

           Debugging output is useful when you suspect a bug in Nping,
           or if you are simply confused as to what Nping is doing and
           why. As this feature is mostly intended for developers, debug
           lines aren't always self-explanatory. You may get something
           like

               NSOCK (1.0000s) Callback: TIMER SUCCESS for EID 12; tcpconnect_event_handler(): Received callback of type TIMER with status SUCCESS

           If you don't understand a line, your only recourses are to
           ignore it, look it up in the source code, or request help
           from the development list (nmap-dev). Some lines are
           self-explanatory, but the messages become more obscure as the
           debug level is increased. These are the available levels:

           Level 0
               Level 0. No debug information at all. This is the default
               level.

           Level 1
               In this level, only very important or high-level debug
               information will be printed.

           Level 2
               Like level 1 but also displays important or medium-level
               debug information

           Level 3
               Like level 2 but also displays regular and low-level
               debug information.

           Level 4
               Like level 3 but also displays messages only a real Nping
               freak would want to see.

           Level 5
               Like level 4 but it enables basic debug information
               related to external libraries like Nsock.

           Level 6
               Like level 5 but it enables full, very detailed, debug
               information related to external libraries like Nsock.

BUGS         top

       Like its authors, Nping isn't perfect. But you can help make it
       better by sending bug reports or even writing patches. If Nping
       doesn't behave the way you expect, first upgrade to the latest
       version available from https://nmap.org . If the problem persists,
       do some research to determine whether it has already been
       discovered and addressed. Try searching for the problem or error
       message on Google since that aggregates so many forums. If
       nothing comes of this, create an Issue on our tracker (‐
       http://issues.nmap.org ) and/or mail a bug report to
       <dev@nmap.org>. If you subscribe to the nmap-dev list before
       posting, your message will bypass moderation and get through more
       quickly. Subscribe at https://nmap.org/mailman/listinfo/dev .
       Please include everything you have learned about the problem, as
       well as what version of Nping you are using and what operating
       system version it is running on. Other suggestions for improving
       Nping may be sent to the Nmap dev mailing list as well.

       If you are able to write a patch improving Nping or fixing a bug,
       that is even better! Instructions for submitting patches or git
       pull requests are available from
       https://github.com/nmap/nmap/blob/master/CONTRIBUTING.md 

       Particularly sensitive issues such as a security reports may be
       sent directly to Fyodor directly at <fyodor@nmap.org>. All other
       reports and comments should use the dev list or issue tracker
       instead because more people read, follow, and respond to those.

AUTHORS         top

       Luis MartinGarcia <luis.mgarc@gmail.com> (http://www.luismg.com )

       Fyodor <fyodor@nmap.org> (https://insecure.org )

NOTES         top

        1. official type numbers assigned by IANA
           http://www.iana.org/assignments/icmp-parameters

        2. official numbers assigned by IANA
           http://www.iana.org/assignments/arp-parameters/

        3. official numbers listed by the IEEE
           http://standards.ieee.org/regauth/ethertype/eth.txt

COLOPHON         top

       This page is part of the nmap (a network scanner) project.
       Information about the project can be found at ⟨http://nmap.org/⟩.
       If you have a bug report for this manual page, send it to
       dev@nmap.org.  This page was obtained from the project's upstream
       Git mirror of the Subversion repository
       ⟨https://github.com/nmap/nmap⟩ on 2023-12-22.  (At that time, the
       date of the most recent commit that was found in the repository
       was 2023-12-14.)  If you discover any rendering problems in this
       HTML version of the page, or you believe there is a better or
       more up-to-date source for the page, or you have corrections or
       improvements to the information in this COLOPHON (which is not
       part of the original manual page), send a mail to
       man-pages@man7.org

Nping                          05/17/2023                       NPING(1)