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TRACEROUTE6(8) FreeBSD System Manager's Manual TRACEROUTE6(8)
NAME
traceroute6 - print the route IPv6 packets will take to a network node
SYNOPSIS
traceroute6 [-adIlnNrSTUv] [-f firsthop] [-g gateway] [-m hoplimit]
[-p port] [-q probes] [-s src] [-t tclass] [-w waittime]
[-A as_server] target [datalen]
DESCRIPTION
The traceroute6 utility uses the IPv6 protocol hop limit field to elicit
an ICMPv6 TIME_EXCEEDED response from each gateway along the path to some
host.
The only mandatory parameter is the destination host name or IPv6
address. The default probe datagram carries 20 bytes of payload, in
addition to the IPv6 header. The size of the payload can be specified by
giving a length (in bytes) after the destination host name.
Other options are:
-a Turn on AS# lookups for each hop encountered.
-A as_server
Turn on AS# lookups and use the given server instead of the
default.
-d Debug mode.
-f firsthop
Specify how many hops to skip in trace.
-g gateway
Specify intermediate gateway. Please note that traceroute6 tries
to use routing headers.
-I Use ICMP6 ECHO instead of UDP datagrams.
-l Print both host hostnames and numeric addresses. Normally
traceroute6 prints only hostnames if -n is not specified, and
only numeric addresses if -n is specified.
-m hoplimit
Specify maximum hoplimit, up to 255. The default is the value of
the net.inet6.ip6.hlim sysctl(8) (the same default used for TCP
connections).
-n Do not resolve numeric address to hostname.
-N Use a packet with no upper layer header for the probes, instead
of UDP datagrams.
-p port
Set SCTP/TCP/UDP port number to port.
-q probes
Set the number of probe per hop count to probes.
-s src Src specifies the source IPv6 address to be used.
-S Use SCTP packets for the probes. The size of probe packets must
be a multiple of 4. If datalen is up to 28, probe packets
consist of a SHUTDOWN-ACK chunk possibly bundled with a PAD
chunk. For larger probe packets, an INIT chunk is used.
-t tclass
tclass specifies the traffic class used when sending probe
packets. The value must be a decimal integer in the range 0 to
255. The default is 0.
-T Use TCP segments for the probes.
-U Use UDP datagrams for the probes. This is the default.
-v Be verbose.
-w waittime
Specify the delay time between probes.
This program prints the route to the given destination and the round-trip
time to each gateway, in the same manner as traceroute.
Here is a list of possible annotations after the round-trip time for each
gateway:
!N Destination Unreachable - No Route to Host.
!P Destination Unreachable - Administratively Prohibited.
!S Destination Unreachable - Not a Neighbour.
!A Destination Unreachable - Address Unreachable.
!H Parameter Problem - Unrecognized Next Header Type.
! This is printed if the hop limit is <= 1 on a port
unreachable message. This means that the packet got to the
destination, but that the reply had a hop limit that was
just large enough to allow it to get back to the source of
the traceroute6. This was more interesting in the IPv4
case, where some IP stack bugs could be identified by this
behaviour.
EXIT STATUS
The traceroute6 utility will exit with 0 on success, and non-zero on
errors.
SEE ALSO
ping(8), traceroute(8)
HISTORY
The traceroute6 utility first appeared in WIDE hydrangea IPv6 protocol
stack kit.
FreeBSD 14.0-RELEASE-p11 November 25, 2020 FreeBSD 14.0-RELEASE-p11