Purpose
Command or Action
(Optional) Specify that encapsulation modification to occur on packets at
ingress.
rewrite ingress tag pop
{
1
|
2
}
symmetric
Step 5
•
pop 1
—
Pop (remove) the outermost tag.
•
pop 2
—
Pop (remove) the two outermost tags.
The
pop2
option is not currently supported on Trunk
EFPs.
Caution
•
symmetric
—
Configure the packet to undergo the reverse of the ingress
action at egress. If a tag is popped at ingress, it is pushed (added) at
egress. This keyword is required for rewrite to function properly.
Configures the router to derive bridge domains from the encapsulation VLAN
list.
bridge-domain bridge-id
Step 6
Return to privileged EXEC mode.
end
Step 7
Verify your entries.
Use one of the following commands
Step 8
•
show ethernetservice instance
•
show bridge-domain [n
|
split-horizon
]
(Optional) Save your entries in the configuration file.
copy running-config startup-config
Step 9
Configuring Asymmetric EFPs
Effective Cisco IOS-XE Release 3.18S, this feature introduces new rewrite rules for the egress direction in
the EFP. You can configure asymmetric rewrite rules in both ingress and egress directions of the EFP.
Encapsulation (EVC filtering) is verified at the egress for these rewrite rules:
•
No rewrite rule
•
Rewrite rule is
rewrite ingress tag push dot1q <value> symmetric
•
Rewrite rule is
rewrite ingress tag push dot1q <value>
•
Rewrite rule is
rewrite egress tag pop 1
Pre-requisites
•
Ensure that split-horizon groups are configured to avoid flooding between EFPs of the same Bridge
Domain (BD).
Carrier Ethernet Configuration Guide (Cisco ASR 920 Series)
24
Ethernet Virtual Connections Configuration
Configuring Asymmetric EFPs
