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
		     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.


	      ignore-df
		     enable IPv4 DF suppression on this tunnel.	 Normally
		     datagrams 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 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.


	      encaplimit ELIM
		     ( only IPv6 tunnels ) set a fixed encapsulation limit.
		     Default 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)