# tc-mpls

## 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
                         filter 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
           encapsulated 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
    


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