1.\" $NetBSD: ping6.8,v 1.22 2002/05/26 13:21:01 itojun Exp $ 2.\" $KAME: ping6.8,v 1.57 2002/05/26 13:18:25 itojun Exp $ 3.\" 4.\" Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 5.\" All rights reserved. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in the 14.\" documentation and/or other materials provided with the distribution. 15.\" 3. Neither the name of the project nor the names of its contributors 16.\" may be used to endorse or promote products derived from this software 17.\" without specific prior written permission. 18.\" 19.\" THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22.\" ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29.\" SUCH DAMAGE. 30.\" 31.Dd May 17, 1998 32.Dt PING6 8 33.Os 34.Sh NAME 35.Nm ping6 36.Nd send 37.Tn ICMPv6 ECHO_REQUEST 38packets to network hosts 39.Sh SYNOPSIS 40.Nm ping6 41.\" without ipsec, or new ipsec 42.Op Fl dfHnNqRtvwW 43.\" old ipsec 44.\" .Op Fl AdEfnNqRtvwW 45.Bk -words 46.Op Fl a Ar addrtype 47.Ek 48.Bk -words 49.Op Fl b Ar bufsiz 50.Ek 51.Bk -words 52.Op Fl c Ar count 53.Ek 54.Bk -words 55.Op Fl g Ar gateway 56.Ek 57.Bk -words 58.Op Fl h Ar hoplimit 59.Ek 60.Bk -words 61.Op Fl I Ar interface 62.Ek 63.Bk -words 64.Op Fl i Ar wait 65.Ek 66.Bk -words 67.Op Fl l Ar preload 68.Ek 69.Bk -words 70.Op Fl p Ar pattern 71.Ek 72.Bk -words 73.\" new ipsec 74.Op Fl P Ar policy 75.Ek 76.Bk -words 77.Op Fl S Ar sourceaddr 78.Ek 79.Bk -words 80.Op Fl s Ar packetsize 81.Ek 82.Bk -words 83.Op Ar hops ... 84.Ek 85.Bk -words 86.Ar host 87.Ek 88.Sh DESCRIPTION 89.Nm 90uses the 91.Tn ICMPv6 92protocol's mandatory 93.Tn ICMP6_ECHO_REQUEST 94datagram to elicit an 95.Tn ICMP6_ECHO_REPLY 96from a host or gateway. 97.Tn ICMP6_ECHO_REQUEST 98datagrams (``pings'') have an IPv6 header, 99and 100.Tn ICMPv6 101header formatted as documented in RFC2463. 102The options are as follows: 103.Bl -tag -width Ds 104.\" old ipsec 105.\" .It Fl A 106.\" Enables transport-mode IPsec authentication header 107.\" .Pq experimental . 108.It Fl a Ar addrtype 109Generate ICMPv6 Node Information Node Addresses query, rather than echo-request. 110.Ar addrtype 111must be a string constructed of the following characters. 112.Bl -tag -width Ds -compact 113.It Ic a 114requests unicast addresses from all of the responder's interfaces. 115If the character is omitted, 116only those addresses which belong to the interface which has the 117responder's address are requests. 118.It Ic c 119requests responder's IPv4-compatible and IPv4-mapped addresses. 120.It Ic g 121requests responder's global-scope addresses. 122.It Ic s 123requests responder's site-local addresses. 124.It Ic l 125requests responder's link-local addresses. 126.It Ic A 127requests responder's anycast addresses. 128Without this character, the responder will return unicast addresses only. 129With this character, the responder will return anycast addresses only. 130Note that the specification does not specify how to get responder's 131anycast addresses. 132This is an experimental option. 133.El 134.It Fl b Ar bufsiz 135Set socket buffer size. 136.It Fl c Ar count 137Stop after sending 138.Pq and receiving 139.Ar count 140.Tn ECHO_RESPONSE 141packets. 142.It Fl d 143Set the 144.Dv SO_DEBUG 145option on the socket being used. 146.\" .It Fl E 147.\" Enables transport-mode IPsec encapsulated security payload 148.\" .Pq experimental . 149.It Fl f 150Flood ping. 151Outputs packets as fast as they come back or one hundred times per second, 152whichever is more. 153For every 154.Tn ECHO_REQUEST 155sent a period 156.Dq \&. 157is printed, while for every 158.Tn ECHO_REPLY 159received a backspace is printed. 160This provides a rapid display of how many packets are being dropped. 161Only the super-user may use this option. 162.Bf -emphasis 163This can be very hard on a network and should be used with caution. 164.Ef 165.It Fl g Ar gateway 166Specifies to use 167.Ar gateway 168as the next hop to the destination. 169The gateway must be a neighbor of the sending node. 170.It Fl H 171Specifies to try reverse-lookup of IPv6 addresses. 172The 173.Nm 174command does not try reverse-lookup unless the option is specified. 175.It Fl h Ar hoplimit 176Set the IPv6 hoplimit. 177.It Fl I Ar interface 178Source packets with the given interface address. 179This flag applies if the ping destination is a multicast address, 180or link-local/site-local unicast address. 181.It Fl i Ar wait 182Wait 183.Ar wait 184seconds 185.Em between sending each packet . 186The default is to wait for one second between each packet. 187This option is incompatible with the 188.Fl f 189option. 190.It Fl l Ar preload 191If 192.Ar preload 193is specified, 194.Nm 195sends that many packets as fast as possible before falling into its normal 196mode of behavior. 197Only the super-user may use this option. 198.It Fl n 199Numeric output only. 200No attempt will be made to lookup symbolic names from addresses in the reply. 201.It Fl N 202Probe node information multicast group 203.Pq Li ff02::2:xxxx:xxxx . 204.Ar host 205must be string hostname of the target 206.Pq must not be a numeric IPv6 address . 207Node information multicast group will be computed based on given 208.Ar host , 209and will be used as the final destination. 210Since node information multicast group is a link-local multicast group, 211outgoing interface needs to be specified by 212.Fl I 213option. 214.It Fl p Ar pattern 215You may specify up to 16 216.Dq pad 217bytes to fill out the packet you send. 218This is useful for diagnosing data-dependent problems in a network. 219For example, 220.Dq Li \-p ff 221will cause the sent packet to be filled with all 222ones. 223.\" new ipsec 224.It Fl P Ar policy 225.Ar policy 226specifies IPsec policy to be used for the probe. 227.It Fl q 228Quiet output. 229Nothing is displayed except the summary lines at startup time and 230when finished. 231.It Fl R 232Make the kernel believe that the target 233.Ar host 234.Po 235or the first 236.Ar hop 237if you specify 238.Ar hops 239.Pc 240is reachable, by injecting upper-layer reachability confirmation hint. 241The option is meaningful only if the target 242.Ar host 243.Pq or the first hop 244is a neighbor. 245.It Fl S Ar sourceaddr 246Specifies the source address of request packets. 247The source address must be one of the unicast addresses of the sending node, 248and must be numeric. 249.It Fl s Ar packetsize 250Specifies the number of data bytes to be sent. 251The default is 56, which translates into 64 252.Tn ICMP 253data bytes when combined 254with the 8 bytes of 255.Tn ICMP 256header data. 257You may need to specify 258.Fl b 259as well to extend socket buffer size. 260.It Fl t 261Generate ICMPv6 Node Information supported query types query, 262rather than echo-request. 263.Fl s 264has no effect if 265.Fl t 266is specified. 267.It Fl v 268Verbose output. 269.Tn ICMP 270packets other than 271.Tn ECHO_RESPONSE 272that are received are listed. 273.It Fl w 274Generate ICMPv6 Node Information DNS Name query, rather than echo-request. 275.Fl s 276has no effect if 277.Fl w 278is specified. 279.It Fl W 280Same as 281.Fl w , 282but with old packet format based on 03 draft. 283This option is present for backward compatibility. 284.Fl s 285has no effect if 286.Fl w 287is specified. 288.It Ar hops 289IPv6 addresses for intermediate nodes, 290which will be put into type 0 routing header. 291.It Ar host 292IPv6 adddress of the final destination node. 293.El 294.Pp 295When using 296.Nm 297for fault isolation, it should first be run on the local host, to verify 298that the local network interface is up and running. 299Then, hosts and gateways further and further away should be 300.Dq pinged . 301Round-trip times and packet loss statistics are computed. 302If duplicate packets are received, they are not included in the packet 303loss calculation, although the round trip time of these packets is used 304in calculating the round-trip time statistics. 305When the specified number of packets have been sent 306.Pq and received 307or if the program is terminated with a 308.Dv SIGINT , 309a brief summary is displayed, showing the number of packets sent and 310received, and the minimum, maximum, mean, and standard deviation of 311the round-trip times. 312.Pp 313This program is intended for use in network testing, measurement and 314management. 315Because of the load it can impose on the network, it is unwise to use 316.Nm 317during normal operations or from automated scripts. 318.\" .Sh ICMP PACKET DETAILS 319.\" An IP header without options is 20 bytes. 320.\" An 321.\" .Tn ICMP 322.\" .Tn ECHO_REQUEST 323.\" packet contains an additional 8 bytes worth of 324.\" .Tn ICMP 325.\" header followed by an arbitrary amount of data. 326.\" When a 327.\" .Ar packetsize 328.\" is given, this indicated the size of this extra piece of data 329.\" .Pq the default is 56 . 330.\" Thus the amount of data received inside of an IP packet of type 331.\" .Tn ICMP 332.\" .Tn ECHO_REPLY 333.\" will always be 8 bytes more than the requested data space 334.\" .Pq the Tn ICMP header . 335.\" .Pp 336.\" If the data space is at least eight bytes large, 337.\" .Nm 338.\" uses the first eight bytes of this space to include a timestamp which 339.\" it uses in the computation of round trip times. 340.\" If less than eight bytes of pad are specified, no round trip times are 341.\" given. 342.Sh DUPLICATE AND DAMAGED PACKETS 343.Nm 344will report duplicate and damaged packets. 345Duplicate packets should never occur when pinging a unicast address, 346and seem to be caused by 347inappropriate link-level retransmissions. 348Duplicates may occur in many situations and are rarely 349.Pq if ever 350a good sign, although the presence of low levels of duplicates may not 351always be cause for alarm. 352Duplicates are expected when pinging a broadcast or multicast address, 353since they are not really duplicates but replies from different hosts 354to the same request. 355.Pp 356Damaged packets are obviously serious cause for alarm and often 357indicate broken hardware somewhere in the 358.Nm 359packet's path 360.Pq in the network or in the hosts . 361.Sh TRYING DIFFERENT DATA PATTERNS 362The 363(inter)network 364layer should never treat packets differently depending on the data 365contained in the data portion. 366Unfortunately, data-dependent problems have been known to sneak into 367networks and remain undetected for long periods of time. 368In many cases the particular pattern that will have problems is something 369that does not have sufficient 370.Dq transitions , 371such as all ones or all zeros, or a pattern right at the edge, such as 372almost all zeros. 373It is not 374necessarily enough to specify a data pattern of all zeros (for example) 375on the command line because the pattern that is of interest is 376at the data link level, and the relationship between what you type and 377what the controllers transmit can be complicated. 378.Pp 379This means that if you have a data-dependent problem you will probably 380have to do a lot of testing to find it. 381If you are lucky, you may manage to find a file that either 382cannot 383be sent across your network or that takes much longer to transfer than 384other similar length files. 385You can then examine this file for repeated patterns that you can test 386using the 387.Fl p 388option of 389.Nm Ns . 390.Sh EXIT STATUS 391.Nm 392exits with 0 on success (the host is alive), 393and non-zero if the arguments are incorrect or the host is not responding. 394.Sh EXAMPLES 395Normally, 396.Nm 397works just like 398.Xr ping 8 399would work; the following will send ICMPv6 echo request to 400.Li dst.foo.com . 401.Bd -literal -offset indent 402ping6 -n dst.foo.com 403.Ed 404.Pp 405The following will probe hostnames for all nodes on the network link attached to 406.Li wi0 407interface. 408The address 409.Li ff02::1 410is named the link-local all-node multicast address, and the packet would 411reach every node on the network link. 412.Bd -literal -offset indent 413ping6 -w ff02::1%wi0 414.Ed 415.Pp 416The following will probe addresses assigned to the destination node, 417.Li dst.foo.com . 418.Bd -literal -offset indent 419ping6 -a agl dst.foo.com 420.Ed 421.Sh SEE ALSO 422.Xr netstat 1 , 423.Xr icmp6 4 , 424.Xr inet6 4 , 425.Xr ip6 4 , 426.Xr ifconfig 8 , 427.Xr ping 8 , 428.Xr routed 8 , 429.Xr traceroute 8 , 430.Xr traceroute6 8 431.Rs 432.%A A. Conta 433.%A S. Deering 434.%T "Internet Control Message Protocol (ICMPv6) for the Internet Protocol Version 6 (IPv6) Specification" 435.%N RFC2463 436.%D December 1998 437.Re 438.Rs 439.%A Matt Crawford 440.%T "IPv6 Node Information Queries" 441.%N draft-ietf-ipngwg-icmp-name-lookups-09.txt 442.%D May 2002 443.%O work in progress material 444.Re 445.Sh HISTORY 446The 447.Xr ping 8 448command appeared in 449.Bx 4.3 . 450The 451.Nm 452command with IPv6 support first appeared in the WIDE Hydrangea IPv6 453protocol stack kit. 454.Sh BUGS 455.\" except for bsdi 456.Nm 457is intentionally separate from 458.Xr ping 8 . 459