tc-vlan (8) - Linux Manuals
tc-vlan: vlan manipulation module
NAME
vlan - vlan manipulation module
SYNOPSIS
tc ... action vlan { pop | pop_eth | PUSH | MODIFY | PUSH_ETH } [ CONTROL ]
PUSH :=
push [ protocol
VLANPROTO ]
[ priority
VLANPRIO ]
id VLANID
MODIFY :=
modify [ protocol
VLANPROTO ]
[ priority
VLANPRIO ]
id VLANID
PUSH_ETH :=
push_eth
dst_mac LLADDR src_mac LLADDR
CONTROL := {
reclassify | pipe | drop | continue | pass | goto chain CHAIN_INDEX }
DESCRIPTION
The vlan action allows to perform 802.1Q en- or decapsulation on a packet, reflected by the operation modes POP, PUSH and MODIFY. The POP mode is simple, as no further information is required to just drop the outer-most VLAN encapsulation. The PUSH and MODIFY modes require at least a VLANID and allow to optionally choose the VLANPROTO to use.The vlan action can also be used to add or remove the base Ethernet header. The pop_eth mode, which takes no argument, is used to remove the base Ethernet header. All existing VLANs must have been previously dropped. The opposite operation, adding a base Ethernet header, is done with the push_eth mode. In that case, the packet must have no MAC header (stacking MAC headers is not permitted). This mode is mostly useful when a previous action has encapsulated the whole original frame behind a network header and one needs to prepend an Ethernet header before forwarding the resulting packet.
OPTIONS
- pop
- Decapsulation mode, no further arguments allowed.
- push
- Encapsulation mode. Requires at least id option.
- modify
- Replace mode. Existing 802.1Q tag is replaced. Requires at least id option.
- pop_eth
- Ethernet header decapsulation mode. Only works on a plain Ethernet header: VLANs, if any, must be removed first.
- push_eth
- Ethernet header encapsulation mode. The Ethertype is automatically set using the network header type. Chaining Ethernet headers is not allowed: the packet must have no MAC header when using this mode. Requires the dst_mac and src_mac options.
- id VLANID
- Specify the VLAN ID to encapsulate into. VLANID is an unsigned 16bit integer, the format is detected automatically (e.g. prefix with '0x' for hexadecimal interpretation, etc.).
- protocol VLANPROTO
- Choose the VLAN protocol to use. At the time of writing, the kernel accepts only 802.1Q or 802.1ad.
- priority VLANPRIO
- Choose the VLAN priority to use. Decimal number in range of 0-7.
- dst_mac LLADDR
- Choose the destination MAC address to use.
- src_mac LLADDR
- Choose the source MAC address to use.
- 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 ICMP packets on eth0 from 10.0.0.2 into VLAN ID 123:
-
#tc qdisc add dev eth0 handle ffff: ingress
#tc filter add dev eth0 parent ffff: pref 11 protocol ip \
Here is an example of the pop function: Incoming VLAN packets on eth0 are decapsulated and the classification process then restarted for the plain packet:
-
#tc qdisc add dev eth0 handle ffff: ingress
#tc filter add dev $ETH parent ffff: pref 1 protocol 802.1Q \
For an example of the pop_eth and push_eth modes, see tc-mpls(8).