Usage Scenario
The peer advertise-ext-community command is used to enable a device to advertise an extended community attribute to a specified peer. If a device advertises an extended community attribute to a specified peer group, all the members of the peer group will inherit the configuration. This simplifies the application of routing policies and facilitates route maintenance and management.
Precautions
Before running the peer advertise-community command to configure a device to advertise a BGP community attribute, you can use a route-policy to define this community attribute.