Local preference of zero

Mahesh Gohil · ‎09-21-2010

Hi experts,

I am having one customer connected to our MPLS PE. we face strange problem of some of the prefix is showing local preference

of zero which is strange b'se no such policy (route-map) is applied to the bgp peering with that customer.

providing few output from PE end

Router#sh run vrf ABC
ip vrf ABC
rd x:x
export map EXPORTS-MAP
route-target export x:x
route-target import x:x
route-target import x:x
maximum routes 10000 80
!
!
!
router bgp 9498
!
address-family ipv4 vrf ABC
no synchronization
bgp dampening 5
redistribute connected route-map SET-COMMUNITY-CONNECTED
redistribute static route-map SET-COMMUNITY-STATIC
neighbor x.x.x.2 remote-as 9730
neighbor x.x.x.2 activate
neighbor x.x.x.2 as-override
neighbor x.x.x.2 prefix-list ABCD in
exit-address-family
!
interface Serial2/0/1.6 point-to-point
ip vrf forwarding ABC
ip address x.x.x.1 255.255.255.252
end

Router#sh ip bgp vpnv4 vrf ABC 10.140.63.0/26
BGP routing table entry for x:x:10.140.63.0/26, version 160176610
Paths: (1 available, best #1, table ABC)
Advertised to update-groups:
     1
64671
    x.x.x.2 from x.x.x.2
      Origin IGP, metric 0, localpref 0, valid, external, best
      Extended Community: RT:x:x
      mpls labels in/out 4416/nolabel

Please let me know if someone has faced similar problem. local pref should be 100 by default but here it seems to be something strange

thanks in advance

milan.kulik · ‎09-22-2010

Hi,

it's also strange I see

Router#sh ip bgp vpnv4 vrf ABC 10.140.63.0/26
BGP routing table entry for x:x:10.140.63.0/26, version 160176610
Paths: (1 available, best #1, table ABC)
Advertised to update-groups:
1
64671
x.x.x.2 from x.x.x.2
Origin IGP, metric 0, localpref 0, valid, external, best
Extended Community: RT:x:x
mpls labels in/out 4416/nolabel

while you are having

neighbor x.x.x.2 remote-as 9730

in your config.

Doesn't the customer use something complex like Route Reflectors to Exchange VPNv4 Routes

(http://www.cisco.com/en/US/docs/ios/12_0s/feature/guide/fsiasl22.html#wp1030302 )

in his network?

BR,

Milan

Mahesh Gohil · ‎09-22-2010

No, it is not correct,

I have changed output you can consider it as 9730.

But it seems this is malfunctioning of router and strange.

let me see if someone has faced similar problem or i will log tac case

thanks for your reply

Regards

mahesh

Mahesh Gohil · ‎11-02-2010

Well guys there is update may be helpful to others

it is declared as bug by cisco: CSCtj23145

and this happens for vrf where we have used export-map and the workaround is to add one more statement in route-map with LP=100

like

route-map permit 40

set local-preference 100

Regards

Mahesh