09-17-2014 10:43 AM - edited 03-04-2019 11:46 PM
Hi, all,
I am seeing a weird BGP path selection problem on 4948 switch running cat4500-entservicesk9-mz.122-46.SG.bin code, this switch has two uplinks to the same ISP's different edge router, one circuit is primary the other one is strict backup, only default route is accepted from ISP. I am setting both local preference and weight to the default route advertised over backup link, however neither one is taking effect, BGP still thinks the backup link is better, what could be wrong?
rtr#sh ip bgp 0.0.0.0/0
BGP routing table entry for 0.0.0.0/0, version 105
Paths: (3 available, best #2, table Default-IP-Routing-Table, not advertised to EBGP peer)
Not advertised to any peer
17675, (received & used)
203.169.8.37 from 203.169.8.37 (61.211.160.150)
Origin IGP, localpref 100, valid, external
Community: 65001:0 no-export
17675
203.169.8.45 from 203.169.8.45 (61.211.160.151)
Origin IGP, localpref 90, weight 90, valid, external, best <====
Community: 65001:0 no-export
17675, (received-only)
203.169.8.45 from 203.169.8.45 (61.211.160.151)
Origin IGP, localpref 100, valid, external
Community: 65001:0 no-export
Thanks
Solved! Go to Solution.
09-17-2014 11:51 AM
Hi,
On cisco routers , weight is having highest preference to decide best path. By default for received route, weight is 0 but you are setting weight 90 to backup path and that is why it is getting preferred (higher is better). Please remove weight and let local preference be 90 (lesser than route on primary path)
--Pls dont forget to rate helpful posts--
Regards,
Akash
09-17-2014 11:51 AM
Hi,
On cisco routers , weight is having highest preference to decide best path. By default for received route, weight is 0 but you are setting weight 90 to backup path and that is why it is getting preferred (higher is better). Please remove weight and let local preference be 90 (lesser than route on primary path)
--Pls dont forget to rate helpful posts--
Regards,
Akash
09-17-2014 11:53 AM
Thanks, somehow I always thought default weight is 100, thanks!
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