3Com 3031 Command Reference Manual page 748

748 C 7: M C C C
HAPTER ULTICAST OMMON ONFIGURATION OMMANDS
By default, no community attribute is advertised to any peer (group).
Example
Advertise community attributes to the peer group named test.
<3Com-bgp-af-mul] peer test advertise-community
peer allow-as-loop Syntax
peer { group-name | peer-address } allow-as-loop asn_limit
undo peer ip-address allow-as-loop asn_limit
View
IPv4 multicast sub-address family view
Parameter
group-name: Peer group name
peer-address: Peer IP address
asn_limit: Acceptable maximum of local AS number in the route update messages
received.
Description
Using the peer allow-as-loop command, you can specify to Using the undo peer
allow-as-loop command, you can specify not to contain the local AS number in
the AS-PATH attributes received, for routing loop should be removed in the route
update messages received in Hub&Spoke networking mode.
By default, the local AS number is unacceptable in the route update messages
received.
For the standard BGP, routing loop test is based on AS numbers. But in
Hub&Spoke networking mode, if EBGP runs between a PE and a CE, the local AS
number is contained in the PE's advertising routing information to the CE. Then
the PE will not be able to receive the update messages for this route.
The peer allow-as-loop command can solve this problem, for it enables to contain
the local AS number in the route update messages received from the CE. The
acceptable maximum of the local AS number is defined via the asn_limit
parameter.
Example
Specify to contain the local AS number in the AS_PATH attributes received.
<3Com-bgp] ipv4-family multicast
<3Com-bgp-af-vpn] peer 1.1.1.1 allow-as-loop 1
peer as-path-acl Syntax
peer { group-name | peer-address } as-path-acl number { import | export }
undo peer { group-name | peer-address } as-path-acl number { import |
export }