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MPLS manipulation action in tc(8)    Linux   MPLS manipulation action in tc(8)
NAME
       mpls - mpls manipulation module
SYNOPSIS
       tc ... action mpls { POP | PUSH | MODIFY | dec_ttl } [ CONTROL ]
       POP := pop protocol MPLS_PROTO
       PUSH  := { push | mac_push } [ protocol MPLS_PROTO ]  [ tc MPLS_TC ]  [
               ttl MPLS_TTL ]  [ bos MPLS_BOS ] label MPLS_LABEL
       MODIFY := modify [ label MPLS_LABEL ]  [ tc MPLS_TC ]  [ ttl MPLS_TTL ]
       CONTROL := { reclassify | pipe | drop | continue | pass  |  goto  chain
               CHAIN_INDEX }
DESCRIPTION
       The  mpls  action  performs  mpls  encapsulation  or decapsulation on a
       packet, reflected by the operation modes POP, PUSH, MODIFY and DEC_TTL.
       The POP mode requires the ethertype of the header that follows the MPLS
       header (e.g.  IPv4 or another MPLS). It  will  remove  the  outer  MPLS
       header  and  replace  the ethertype in the MAC header with that passed.
       The PUSH and MODIFY modes update the current MPLS header information or
       add  a  new  header.   PUSH  requires  at least an MPLS_LABEL.  DEC_TTL
       requires no arguments and simply subtracts 1 from the MPLS  header  TTL
       field.
OPTIONS
       pop    Decapsulation mode. Requires the protocol of the next header.
       push   Encapsulation mode. Adds the MPLS header between the MAC and the
              network headers. Requires at least the label option.
       mac_push
              Encapsulation mode. Adds the MPLS header before the MAC  header.
              Requires at least the label option.
       modify Replace mode. Existing MPLS tag is replaced.  label, tc, and ttl
              are all optional.
       dec_ttl
              Decrement the TTL field on the outer most MPLS header.
       label MPLS_LABEL
              Specify the MPLS LABEL for the outer MPLS header.  MPLS_LABEL is
              an  unsigned 20bit integer, the format is detected automatically
              (e.g. prefix with '0x' for hexadecimal interpretation, etc.).
       protocol MPLS_PROTO
              Choose the protocol to  use.  For  push  actions  this  must  be
              mpls_uc  or mpls_mc (mpls_uc is the default). For pop actions it
              should be the protocol of the next header.  This  option  cannot
              be used with modify.
       tc MPLS_TC
              Choose the TC value for the outer MPLS header. Decimal number in
              range of 0-7.  Defaults to 0.
       ttl MPLS_TTL
              Choose the TTL value for the outer MPLS header. Number in  range
              of  0-255.  A non-zero default value will be selected if this is
              not explicitly set.
       bos MPLS_BOS
              Manually configure the bottom of stack bit for  an  MPLS  header
              push.  The default is for TC to automatically set (or unset) the
              bit based on the next header of the packet.
       CONTROL
              How to continue after executing this action.
              reclassify
                     Restarts classification by jumping back to the first fil-
                     ter attached to this action's parent.
              pipe   Continue with the next action, this is the default.
              drop   Packet will be dropped without running further actions.
              continue
                     Continue classification with next filter in line.
              pass   Return  to calling qdisc for packet processing. This ends
                     the classification process.
EXAMPLES
       The following example encapsulates incoming IP  packets  on  eth0  into
       MPLS with a label 123 and sends them out eth1:
              #tc qdisc add dev eth0 handle ffff: ingress
              #tc filter add dev eth0 protocol ip parent ffff: flower \
                   action mpls push protocol mpls_uc label 123  \
                   action mirred egress redirect dev eth1
       In this example, incoming MPLS unicast packets on eth0 are decapsulated
       and redirected to eth1:
              #tc qdisc add dev eth0 handle ffff: ingress
              #tc filter add dev eth0 protocol mpls_uc parent ffff: flower \
                   action mpls pop protocol ipv4  \
                   action mirred egress redirect dev eth1
       Here is another example, where incoming Ethernet  frames  are  encapsu-
       lated  into  MPLS  with  label  123 and TTL 64. Then, an outer Ethernet
       header is added and the resulting frame is finally sent on eth1:
              #tc qdisc add dev eth0 ingress
              #tc filter add dev eth0 ingress matchall \
                   action mpls mac_push label 123 ttl 64 \
                   action vlan push_eth \
                        dst_mac 02:00:00:00:00:02 \
                        src_mac 02:00:00:00:00:01 \
                   action mirred egress redirect dev eth1
       The following example assumes that incoming MPLS packets with label 123
       transport  Ethernet frames. The outer Ethernet and the MPLS headers are
       stripped, then the inner Ethernet frame is sent on eth1:
              #tc qdisc add dev eth0 ingress
              #tc filter add dev eth0 ingress protocol mpls_uc \
                   flower mpls_label 123 mpls_bos 1 \
                   action vlan pop_eth \
                   action mpls pop protocol teb \
                   action mirred egress redirect dev eth1
SEE ALSO
       tc(8), tc-mirred(8), tc-vlan(8)
iproute2                          22 May 2019MPLS manipulation action in tc(8)