Tag-Stripping Overview

Understand how policies are used to strip header tags.

Stripping encapsulation header tags prepares them for downstream analytic and other monitoring tools. Header-tag stripping at egress is applied on only the first L2 header of the received packet.

You configure a listener policy to define the actions to be performed on packet header tags, which you then bind to an egress policy. A listener policy supports the following header-modification and traffic actions.

• 802.1BR
• VN-TAG
• VLAN

You can create multiple listener-policy stanzas, but they do not have to be used in unique 1:1 configurations, as demonstrated in the following example to manage different traffic types. In the following example, two listener policies (cow and smurf) are used to manage three traffic types.

• Listener-policy cow has two entries:
  • One manages 802.1BR traffic.
  • One manages VN-TAG traffic.

Table 1. Example: Listener-policy use for traffic types

Example 1	Example 2	Example 3
listener-policy lp-1 10 match ip access-list v4_someacl1 strip br-tag	listener-policy lp-1 20 match ip access-list v4_someacl2 strip vn-tag	listener-policy lp-2 10 match ip access-list v4_someacl1 strip vn-tag

The following table lists the minimum requirements that must be configured for each policy type.