1.\" $KAME: traceroute6.8,v 1.10 2004/06/06 12:35:15 suz Exp $ 2.\" 3.\" Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 4.\" All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. Neither the name of the project nor the names of its contributors 15.\" may be used to endorse or promote products derived from this software 16.\" without specific prior written permission. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 19.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21.\" ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 22.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28.\" SUCH DAMAGE. 29.\" 30.Dd November 25, 2020 31.Dt TRACEROUTE6 8 32.Os 33.\" 34.Sh NAME 35.Nm traceroute6 36.Nd "print the route IPv6 packets will take to a network node" 37.\" 38.Sh SYNOPSIS 39.Nm 40.Bk -words 41.Op Fl adIlnNrSTUv 42.Ek 43.Bk -words 44.Op Fl f Ar firsthop 45.Ek 46.Bk -words 47.Op Fl g Ar gateway 48.Ek 49.Bk -words 50.Op Fl m Ar hoplimit 51.Ek 52.Bk -words 53.Op Fl p Ar port 54.Ek 55.Bk -words 56.Op Fl q Ar probes 57.Ek 58.Bk -words 59.Op Fl s Ar src 60.Ek 61.Bk -words 62.Op Fl t Ar tclass 63.Ek 64.Bk -words 65.Op Fl w Ar waittime 66.Ek 67.Bk -words 68.Op Fl A Ar as_server 69.Ek 70.Bk -words 71.Ar target 72.Op Ar datalen 73.Ek 74.\" 75.Sh DESCRIPTION 76The 77.Nm 78utility 79uses the IPv6 protocol hop limit field to elicit an ICMPv6 TIME_EXCEEDED 80response from each gateway along the path to some host. 81.Pp 82The only mandatory parameter is the destination host name or IPv6 address. 83The default probe datagram carries 20 bytes of payload, 84in addition to the IPv6 header. 85The size of the payload can be specified by giving a length 86(in bytes) 87after the destination host name. 88.Pp 89Other options are: 90.Bl -tag -width Ds 91.It Fl a 92Turn on AS# lookups for each hop encountered. 93.It Fl A Ar as_server 94Turn on AS# lookups and use the given server instead of the default. 95.It Fl d 96Debug mode. 97.It Fl f Ar firsthop 98Specify how many hops to skip in trace. 99.It Fl g Ar gateway 100Specify intermediate gateway. 101Please note that 102.Nm 103tries to use routing headers. 104.It Fl I 105Use ICMP6 ECHO instead of UDP datagrams. 106.It Fl l 107Print both host hostnames and numeric addresses. 108Normally 109.Nm 110prints only hostnames if 111.Fl n 112is not specified, and only numeric addresses if 113.Fl n 114is specified. 115.It Fl m Ar hoplimit 116Specify maximum hoplimit, up to 255. 117The default is the value of the 118.Va net.inet6.ip6.hlim 119.Xr sysctl 8 120(the same default used for TCP connections). 121.It Fl n 122Do not resolve numeric address to hostname. 123.It Fl N 124Use a packet with no upper layer header for the probes, 125instead of UDP datagrams. 126.It Fl p Ar port 127Set SCTP/TCP/UDP port number to 128.Ar port . 129.It Fl q Ar probes 130Set the number of probe per hop count to 131.Ar probes . 132.It Fl r 133Bypass the normal routing tables and send directly to a host 134on an attached network. 135If the host is not on a directly-connected network, 136an error is returned. 137This option corresponds to the 138.Dv SO_DONTROUTE 139socket option; 140it can be used to ping a local host through an interface 141that has no route through it 142(e.g., after the interface was dropped by a routing daemon). 143.It Fl s Ar src 144.Ar Src 145specifies the source IPv6 address to be used. 146.It Fl S 147Use SCTP packets for the probes. 148The size of probe packets must be a multiple of 4. 149If 150.Ar datalen 151is up to 28, probe packets consist of a SHUTDOWN-ACK chunk possibly bundled 152with a PAD chunk. 153For larger probe packets, an INIT chunk is used. 154.It Fl t Ar tclass 155.Ar tclass 156specifies the 157.Em traffic class 158used when sending probe packets. 159The value must be a decimal integer in the range 0 to 255. 160The default is 0. 161.It Fl T 162Use TCP segments for the probes. 163.It Fl U 164Use UDP datagrams for the probes. 165This is the default. 166.It Fl v 167Be verbose. 168.It Fl w Ar waittime 169Specify the delay time between probes. 170.El 171.Pp 172This program prints the route to the given destination and the round-trip 173time to each gateway, in the same manner as traceroute. 174.Pp 175Here is a list of possible annotations after the round-trip time for each gateway: 176.Bl -hang -offset indent 177.It !N 178Destination Unreachable - No Route to Host. 179.It !P 180Destination Unreachable - Administratively Prohibited. 181.It !S 182Destination Unreachable - Not a Neighbour. 183.It !A 184Destination Unreachable - Address Unreachable. 185.It !H 186Parameter Problem - Unrecognized Next Header Type. 187.It !\& 188This is printed if the hop limit is <= 1 on a port unreachable message. 189This means that the packet got to the destination, 190but that the reply had a hop limit that was just large enough to 191allow it to get back to the source of the traceroute6. 192This was more interesting in the IPv4 case, 193where some IP stack bugs could be identified by this behaviour. 194.El 195.\" 196.Sh EXIT STATUS 197The 198.Nm 199utility will exit with 0 on success, and non-zero on errors. 200.\" 201.Sh SEE ALSO 202.Xr ping 8 , 203.Xr traceroute 8 204.\" 205.Sh HISTORY 206The 207.Nm 208utility first appeared in WIDE hydrangea IPv6 protocol stack kit. 209