Neighbor: Specifying The Source For Updates - HP 7102dl - ProCurve Secure Router Configuration Manual

IP Routing—Configuring RIP, OSPF, BGP, and PBR
Configuring BGP
Balancing Loads over Multiple Connections to the Same Neighbor:
Specifying the Source for Updates
If you are connecting to the neighbor using T1 or E1 lines over a PPP or
Frame Relay connection, you do not need to configure load balancing. You
should instead configure Multilink PPP (MLPPP) or Multilink Frame Relay
(MLFR), protocols that automatically distribute traffic over multiple carrier
lines. (See Chapter 2: Increasing Bandwidth.)
Otherwise, you can effectively force the router to balance traffic between two
connections to the same neighbor by specifying the loopback interface as the
update source.
To configure the update source, move to the BGP neighbor configuration
mode context and enter:
Syntax: update-source <interface ID>
In this situation, you should enter:
ProCurve(config-bgp-neighbor)# update-source loopback 1
When the ProCurve Secure Router receives a route from a neighbor, it sets the
update source as the forwarding interface for the route. Because the loopback
interface becomes the forwarding interface rather than a specific WAN inter-
face, the router automatically distributes packets over all links to the neighbor.
A loopback interface also adds stability to the network because it is always
up as long as a path exists between the router and the neighbor. In this way,
the router sidesteps problems with unstable links or flapping interfaces.
Hop 1 Hop 2
WAN
interface
ISP
Router A
Network 1
Loopback
interface
Figure 15-16. EBGP Multihop
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