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New Member

Lost in BGP

hi all. am a BGP beginner. using GNS3 i tried to configure BGP but the internal router is not trusting the route coming from its nei in the same AS. i used the route-reflector command, it didnt work also tried the next-hop-self command but didnt work also. please can i get direction on how to go about it. thanks all

9 REPLIES
Hall of Fame Super Silver

Re: Lost in BGP

Hello Jay,

you probably need to disable synchronization if the route is not advertised in a IGP

router bgp xx

no sync

With sync on (default) the iBGP route is accepted, installed and advertised if it is known in the IGP in use (OSPF, EIGRP ...)

Hope to help

Giuseppe

Cisco Employee

Re: Lost in BGP

Giuseppe,

Just one precision. The default is now to have synchronization disabled by default. That has been changed a long time ago (12.2T I believe).

Synchronization might still be the issue depending on the software version that was used in this specific case.

Regards

Harold Ritter
Sr. Technical Leader
CCIE 4168 (R&S, SP)
harold@cisco.com
México móvil: +52 1 55 8312 4915
Cisco México 
Paseo de la Reforma 222 Piso 19
Cuauhtémoc, Juárez
Ciudad de México, 06600
México
Hall of Fame Super Silver

Re: Lost in BGP

Hello Harold,

thanks I had missed the change

10.0

This command was introduced.

12.0(7)T

Address family configuration mode was added.

>>>12.2(8)T

>>>Command default behavior changed to disabled.

http://www.cisco.com/en/US/docs/ios/iproute/command/reference/irp_bgp5.html#wp1018615

Best Regards

Giuseppe

New Member

Re: Lost in BGP

oh thanks for your support. i have been able to rectify the problem but another problem now comes up. i see this sign r> on routes coming from an internal router in the same AS. what does it mean?

New Member

Re: Lost in BGP

oh thanks for your support. i have been able to rectify the problem but another problem now comes up. i see this sign r> on routes coming from an internal router in the same AS. what does it mean?

Cisco Employee

Re: Lost in BGP

Jerome,

Can you provide a "show ip bgp " for the specific prefix that is not accepted. This should tell you what is causing the issue.

Regards

Harold Ritter
Sr. Technical Leader
CCIE 4168 (R&S, SP)
harold@cisco.com
México móvil: +52 1 55 8312 4915
Cisco México 
Paseo de la Reforma 222 Piso 19
Cuauhtémoc, Juárez
Ciudad de México, 06600
México
New Member

Re: Lost in BGP

oh thanks for your support. i have been able to rectify the problem but another problem now comes up. i see this sign r> on routes coming from an internal router in the same AS. what does it mean?

Hall of Fame Super Silver

Re: Lost in BGP

Hello Jay,

a r sign means that the route is received but it is regarded as not totally correct

r means RIB failure.

It may mean the local router has a better route for the prefix then the one received in iBGP

try to compare

sh ip bgp

and

sh ip route

Hope to help

Giuseppe

New Member

Re: Lost in BGP

thanks giuseppe. the meaning was a lower cost route was present in the IP routing table. you are the best.

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