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.\" $FreeBSD$ 31.\" 32.Dd July 16, 2019 33.Dt TRACEROUTE6 8 34.Os 35.\" 36.Sh NAME 37.Nm traceroute6 38.Nd "print the route IPv6 packets will take to a network node" 39.\" 40.Sh SYNOPSIS 41.Nm 42.Bk -words 43.Op Fl adIlnNrSTUv 44.Ek 45.Bk -words 46.Op Fl f Ar firsthop 47.Ek 48.Bk -words 49.Op Fl g Ar gateway 50.Ek 51.Bk -words 52.Op Fl m Ar hoplimit 53.Ek 54.Bk -words 55.Op Fl p Ar port 56.Ek 57.Bk -words 58.Op Fl q Ar probes 59.Ek 60.Bk -words 61.Op Fl s Ar src 62.Ek 63.Bk -words 64.Op Fl w Ar waittime 65.Ek 66.Bk -words 67.Op Fl A Ar as_server 68.Ek 69.Bk -words 70.Ar target 71.Op Ar datalen 72.Ek 73.\" 74.Sh DESCRIPTION 75The 76.Nm 77utility 78uses the IPv6 protocol hop limit field to elicit an ICMPv6 TIME_EXCEEDED 79response from each gateway along the path to some host. 80.Pp 81The only mandatory parameter is the destination host name or IPv6 address. 82The default probe datagram carries 20 bytes of payload, 83in addition to the IPv6 header. 84The size of the payload can be specified by giving a length 85(in bytes) 86after the destination host name. 87.Pp 88Other options are: 89.Bl -tag -width Ds 90.It Fl a 91Turn on AS# lookups for each hop encountered. 92.It Fl A Ar as_server 93Turn on AS# lookups and use the given server instead of the default. 94.It Fl d 95Debug mode. 96.It Fl f Ar firsthop 97Specify how many hops to skip in trace. 98.It Fl g Ar gateway 99Specify intermediate gateway. Please note that 100.Nm 101tries to use routing headers. 102.It Fl I 103Use ICMP6 ECHO instead of UDP datagrams. 104.It Fl l 105Print both host hostnames and numeric addresses. 106Normally 107.Nm 108prints only hostnames if 109.Fl n 110is not specified, and only numeric addresses if 111.Fl n 112is specified. 113.It Fl m Ar hoplimit 114Specify maximum hoplimit, up to 255. 115The default is the value of the 116.Va net.inet6.ip6.hlim 117.Xr sysctl 8 118(the same default used for TCP connections). 119.It Fl n 120Do not resolve numeric address to hostname. 121.It Fl N 122Use a packet with no upper layer header for the probes, 123instead of UDP datagrams. 124.It Fl p Ar port 125Set SCTP/TCP/UDP port number to 126.Ar port . 127.It Fl q Ar probes 128Set the number of probe per hop count to 129.Ar probes . 130.It Fl r 131Bypass the normal routing tables and send directly to a host 132on an attached network. 133If the host is not on a directly-connected network, 134an error is returned. 135This option corresponds to the 136.Dv SO_DONTROUTE 137socket option; 138it can be used to ping a local host through an interface 139that has no route through it 140(e.g., after the interface was dropped by a routing daemon). 141.It Fl s Ar src 142.Ar Src 143specifies the source IPv6 address to be used. 144.It Fl S 145Use SCTP packets for the probes. 146The size of probe packets must be a multiple of 4. 147If 148.Ar datalen 149is up to 28, probe packets consist of a SHUTDOWN-ACK chunk possibly bundled 150with a PAD chunk. For larger probe packets, an INIT chunk is used. 151.It Fl T 152Use TCP segments for the probes. 153.It Fl U 154Use UDP datagrams for the probes. 155This is the default. 156.It Fl v 157Be verbose. 158.It Fl w Ar waittime 159Specify the delay time between probes. 160.El 161.Pp 162This program prints the route to the given destination and the round-trip 163time to each gateway, in the same manner as traceroute. 164.Pp 165Here is a list of possible annotations after the round-trip time for each gateway: 166.Bl -hang -offset indent 167.It !N 168Destination Unreachable - No Route to Host. 169.It !P 170Destination Unreachable - Administratively Prohibited. 171.It !S 172Destination Unreachable - Not a Neighbour. 173.It !A 174Destination Unreachable - Address Unreachable. 175.It !H 176Parameter Problem - Unrecognized Next Header Type. 177.It !\& 178This is printed if the hop limit is <= 1 on a port unreachable message. 179This means that the packet got to the destination, 180but that the reply had a hop limit that was just large enough to 181allow it to get back to the source of the traceroute6. 182This was more interesting in the IPv4 case, 183where some IP stack bugs could be identified by this behaviour. 184.El 185.\" 186.Sh EXIT STATUS 187The 188.Nm 189utility will exit with 0 on success, and non-zero on errors. 190.\" 191.Sh SEE ALSO 192.Xr ping 8 , 193.Xr ping6 8 , 194.Xr traceroute 8 195.\" 196.Sh HISTORY 197The 198.Nm 199utility first appeared in WIDE hydrangea IPv6 protocol stack kit. 200