IP-TUNNEL(8) Linux IP-TUNNEL(8)
NAME
ip-tunnel - tunnel configuration
SYNOPSIS
ip tunnel help
ip [ OPTIONS ] tunnel { add | change | del | show | prl | 6rd } [ 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 ]
[ 6rd-prefix ADDR ] [ 6rd-relay_prefix ADDR ] [ 6rd-reset ]
[ [no]pmtudisc ] [ [no]ignore-df ] [ [no]allow-localremote ]
[ 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 }
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 encap-
sulating 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 spe-
cial value meaning that packets inherit the TTL value.
The default value for IPv4 tunnels is: inherit. The de-
fault 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 ei-
ther 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 de-
fault value is 00.
dev NAME
bind the tunnel to the device NAME so that tunneled pack-
ets will only be routed via this device and will not be
able to escape to another device when the route to end-
point 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.
ignore-df
enable IPv4 DF suppression on this tunnel. Normally data-
grams that exceed the MTU will be fragmented; the presence
of the DF flag inhibits this, resulting instead in an ICMP
Unreachable (Fragmentation Required) message. Enabling
this attribute causes the DF flag to be ignored.
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 para-
meter sets the key to use in both directions. The ikey
and okey parameters set different keys for input and out-
put.
csum, icsum, ocsum
( only GRE tunnels ) generate/require checksums for tun-
neled 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 equiv-
alent to the combination icsum ocsum.
seq, iseq, oseq
( only GRE tunnels ) serialize packets. The oseq flag en-
ables sequencing of outgoing packets. The iseq flag re-
quires that all input packets are serialized. The seq
flag is equivalent to the combination iseq oseq. It
doesn't work. Don't use it.
encaplimit ELIM
( only IPv6 tunnels ) set a fixed encapsulation limit. De-
fault is 4.
flowlabel FLOWLABEL
( only IPv6 tunnels ) set a fixed flowlabel.
allow-localremote
( only IPv6 tunnels ) allow remote endpoint on the local
host.
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>
iproute2 20 Dec 2011 IP-TUNNEL(8)
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