ip-tunnel(8)
NAME
ip-tunnel - tunnel configuration
SYNOPSIS
ip tunnel help
ip [ OPTIONS ] tunnel { add | change | del | show | prl } [ NAME ]
[ mode MODE ] [ remote ADDR ] [ local ADDR ]
[ [i|o]seq ] [ [i|o]key KEY ] [ [i|o]csum ] ]
[ encaplimit ELIM ] [ ttl|hoplimit TTL ]
[ tos TOS ] [ flowlabel FLOWLABEL ]
[ prl-default ADDR ] [ prl-nodefault ADDR ] [ prl-delete ADDR ]
[ [no]pmtudisc ] [ dev PHYS_DEV ]
MODE := { ipip | gre | sit | isatap | vti | ip6ip6 | ipip6 | ip6gre |
vti6 | any }
ADDR := { IP_ADDRESS | any }
TOS := { STRING | 00..ff | inherit | inherit/STRING | inherit/00..ff }
ELIM := { none | 0..255 }
TTL := { 1..255 | inherit }
KEY := { DOTTED_QUAD | NUMBER }
TIME := NUMBER[s|ms]
DESCRIPTION
tunnel objects are tunnels, encapsulating packets in IP packets and
then sending them over the IP infrastructure. The encapsulating (or
outer) address family is specified by the -f option. The default is
IPv4.
ip tunnel add
add a new tunnel
ip tunnel change
change an existing tunnel
ip tunnel delete
destroy a tunnel
name NAME (default)
select the tunnel device name.
mode MODE
set the tunnel mode. Available modes depend on the
encapsulating address family.
Modes for IPv4 encapsulation available: ipip, sit,
isatap, vti, and gre.
Modes for IPv6 encapsulation available: ip6ip6, ipip6,
ip6gre, vti6, and any.
remote ADDRESS
set the remote endpoint of the tunnel.
local ADDRESS
set the fixed local address for tunneled packets. It
must be an address on another interface of this host.
ttl N
hoplimit N
set a fixed TTL (IPv4) or hoplimit (IPv6) N on tunneled
packets. N is a number in the range 1--255. 0 is a
special value meaning that packets inherit the TTL value.
The default value for IPv4 tunnels is: inherit. The
default value for IPv6 tunnels is: 64.
tos T
dsfield T
tclass T
set the type of service (IPv4) or traffic class (IPv6)
field on tunneled packets, which can be specified as
either a two-digit hex value (e.g. c0) or a predefined
string (e.g. internet). The value inherit causes the
field to be copied from the original IP header. The
values inherit/STRING or inherit/00..ff will set the
field to STRING or 00..ff when tunneling non-IP packets.
The default value is 00.
dev NAME
bind the tunnel to the device NAME so that tunneled
packets will only be routed via this device and will not
be able to escape to another device when the route to
endpoint changes.
nopmtudisc
disable Path MTU Discovery on this tunnel. It is enabled
by default. Note that a fixed ttl is incompatible with
this option: tunneling with a fixed ttl always makes pmtu
discovery.
key K
ikey K
okey K ( only GRE tunnels ) use keyed GRE with key K. K is
either a number or an IP address-like dotted quad. The
key parameter sets the key to use in both directions.
The ikey and okey parameters set different keys for input
and output.
csum, icsum, ocsum
( only GRE tunnels ) generate/require checksums for
tunneled packets. The ocsum flag calculates checksums
for outgoing packets. The icsum flag requires that all
input packets have the correct checksum. The csum flag is
equivalent to the combination icsum ocsum.
seq, iseq, oseq
( only GRE tunnels ) serialize packets. The oseq flag
enables sequencing of outgoing packets. The iseq flag
requires that all input packets are serialized. The seq
flag is equivalent to the combination iseq oseq. It
doesn't work. Don't use it.
encaplim ELIM
( only IPv6 tunnels ) set a fixed encapsulation limit.
Default is 4.
flowlabel FLOWLABEL
( only IPv6 tunnels ) set a fixed flowlabel.
ip tunnel prl
potential router list (ISATAP only)
dev NAME
mandatory device name.
prl-default ADDR
prl-nodefault ADDR
prl-delete ADDR
Add or delete ADDR as a potential router or default
router.
ip tunnel show
list tunnels This command has no arguments.
SEE ALSO
ip(8)
AUTHOR
Original Manpage by Michail Litvak <mci@owl.openwall.com>
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