ip-tunnel - tunnel configuration


   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 }


   TIME := NUMBER[s|ms]


   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

   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.

                 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

          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

   ip tunnel show
          list tunnels This command has no arguments.




   Original Manpage by Michail Litvak <mci@owl.openwall.com>


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