Peer As-Number - 3Com 8807 Command Reference Manual

LDP Configuration Commands 729
Description
Use the peer allow-as-loop command to allow loop in the route updates in the
Hub & Spoke networking mode.
Use the undo peer allow-as-loop command to prohibit loop in the route
updates.
By default, loop is prohibited in the received routing updates; by using the peer
allow-as-loop command, loop is allowed in the received routing updates. The
default value of asn-limit argument is 3.
Standard BGP tests loop using AS number. However, on a Hub & Spoke network
running EBGP between PE and CE, PE carries its own AS number when advertising
route information to CE. Accordingly, the updated route information will contain
PE's AS number when it is sent from CE. In this case, PE will not accept the route
updates.
You can avoid this by using the peer allow-as-loop command, which makes PE
router allow the route updates from CE to contain its AS number. You can define
asn-imit to control the maximum times for which AS number is received by PE.
Example
# Enable route loop.
[3Com-bgp] ipv4-family vpnv4
[3Com-bgp-af-vpn] peer 1.1.1.1 allow-as-loop 1

peer as-number

Syntax
peer { group-name | [ peer-address group group-name ] }as-number as-number
undo peer { group-name | [ peer-address group group-name ] }as-number
as-number
View
VPN-instance sub-address family view
Parameter
group-name: Name of a peer group, consisting of 1 to 47 alphanumeric
characters.
peer-address: IP address of peer group.
as-number: Opposite AS number of a peer (group).
Description
Use the peer as-number command to configure the opposite AS number of a
specified peer (group).
Use the undo peer as-number command to remove the opposite AS number of
a specified peer (group).
By default, the opposite end of a peer (group) has no AS number.