EFPs that are not configured with an explicit
group_id
do not belong to any group.
You can configure no more than 128 service instances per bridge domain. These 128 EFPs can be distributed
among split-horizon groups 0 to 13.
VPLS uses a reserved internal split group 15 which does not overlap with manually configured split groups.
In case VPLS is configured on same bridge domain, scale of 128 EFPs can still be achieved on the same
bridge domain.
128 EFPs and 64 VFIs are supported on the same bridge domain.
Restrictions
•
Maximum number of EFPs per bridge-domain is 128. The EFPs can be distributed among split-horizon
groups 0 to 13.
•
VPLS uses the reserved internal Split-horizon group 15 which
does not
overlap with manually configured
split groups. In case VPLS is configured on the same bridge-domain, the scale of 128 EFPs is achieved
on the same bridge-domain.
•
64 VFIs are supported on the same bridge-domain.
Rewrite Operations
You can use the
rewrite
command to modify packet VLAN tags. You can use this command to emulate
traditional 802.1Q tagging, where packets enter a router on the native VLAN and VLAN tagging properties
are added on egress. You can also use the
rewrite
command to facilitate VLAN translation and QinQ.
The supported
rewrite
commands:
•
rewrite ingress tag pop 1 symmetric
•
rewrite ingress tag pop 2 symmetric
•
rewrite ingress tag push dot1q vlan-id symmetric
Enter the
rewrite ingress tag pop
{
1
|
2
}
symmetric
service-instance configuration mode command to specify
the encapsulation adjustment to be performed on the frame ingress to the EFP. Entering
pop 1
pops (removes)
the outermost tag; entering
pop 2
removes two outermost tags.
The
symmetric
keyword is required to complete
rewrite
to configuration.
Note
When you enter the
symmetric
keyword, the egress counterpart performs the inverse action and pushes (adds)
the encapsulation VLAN. You can use the
symmetric
keyword only with ingress rewrites and only when
single VLANs are configured in encapsulation. If you configure a list of VLANs or a VLAN range or
encapsulation default
or
encapsulation any
, the
symmetric
keyword is not accepted for rewrite operations.
Static MAC Addresses
The router supports multicast static MAC addresses, which allow you to enable multicast at the layer 2 level.
You can use multicast static MAC addresses to forward multicast packets to specific EFPs on a network.
Carrier Ethernet Configuration Guide (Cisco ASR 920 Series)
19
Ethernet Virtual Connections Configuration
Rewrite Operations
