Cisco: BGP Multipath Loadbalancing maximum-paths
sumber: https://learningnetwork.cisco.com/thread/42531
have read that BGP does not really support load balancing, but now I have discovered the BGP maximum-paths command.
maximum-paths (BGP)
To control the maximum number of parallel routes that the Border Gateway Protocol (BGP) can support, use the maximum-paths command. To restore the default number of parallel routes, use the no form of this command.
maximum-paths [ ibgp ] number-paths no maximum-paths [ ibgp ] number-paths
For instance, consider the following single multihomed design:
As an example, a default route can be received from ISP1 and ISP2 with the same AS_Path, origin code and metric. Thus, both default routes tie by step 8 (according Odom's CCNP Route book) and configuring 'maximum-paths 2' under the bgp process I think I can load balance traffic between ISP1 and ISP2.
So, in the end, does BGP support load balancing considering this command?
router bgp 100 no synchronization bgp log-neighbor-changes network 192.168.0.0 network 192.168.1.0 neighbor 10.0.0.1 remote-as 200 neighbor 172.16.0.1 remote-as 300 maximum-paths 2 no auto-summary
From Odom's CCNP Route book:
If the BGP best path algorithm does not choose a best path by Step 8 (per the numbering in this book), the routes which still tie for being best path through Step 8 will be allowed into the IP routing table, up to the number defined by the BGP maximum-paths number-of-paths router subcommand.
Alternatif Lain
Perintah
bgp bestpath as-path multipath-relax
This will allow the router to load-share across multiple BGP paths even if the as-path is different.