On the routers you are having problems with, can you ping to the loopback
address of the router you are trying to peer with, sourced from your own
loopback?

 

Regards,

Joe Astorino
CCIE #24347 (R&S)
Sr. Support Engineer - IPexpert, Inc.
URL: http://www.IPexpert.com
  

From: [email protected]
[mailto:[email protected]] On Behalf Of Bauke Dzavhale
Sent: Monday, June 15, 2009 10:11 PM
To: [email protected]
Subject: [OSL | CCIE_RS] LAB 9- Vol 2- Task 4-1 (R6 peering with R7 and R9)

 


Team,

I am buffled....


This seems to be a fairly simple eBGP peering config but is NOT working. I
am sure I am missing something here.  The stange thing is R6 can
successfully peer with R9 but can not peer with R7.  And R7  is NOT peering
with R6 (obvious) and neither with R8. All these configs are eBGP just like
R6<===>R9 that is successful. 

Here is the relevant config snapshot.

 

R6

R6 config when peering with R7 and R9.

 

router bgp 245

neighbor 100.0.0.9 remote-as 900
neighbor 100.0.0.9 ebgp-multihop 255
neighbor 100.0.0.9 update-source Loopback1
! This works just fine....

 

neighbor 100.0.0.7 remote-as 700
neighbor 100.0.0.7 ebgp-multihop 255
neighbor 100.0.0.7 update-source Loopback1

! Nop.... 

 

R7

...and R7 config when peering with R6 and R8

 

router bgp 700
neighbor 100.0.0.6 remote-as 245
neighbor 100.0.0.6 ebgp-multihop 255
neighbor 100.0.0.6 update-source Loopback1
! Nop...

 

neighbor 100.0.0.8 remote-as 800
neighbor 100.0.0.8 ebgp-multihop 255
neighbor 100.0.0.8 update-source Loopback1

! Nop...

 

R8

... and the ebgp config when R8 is peering with R7

 

router bgp 800

neighbor 100.0.0.7 remote-as 700
neighbor 100.0.0.7 ebgp-multihop 255
neighbor 100.0.0.7 update-source Loopback1

! of course Nop...

--------------------------------------------------------------------

... and finally R9 when peering with R6

 

router bgp 900

neighbor 100.0.0.6 remote-as 245
neighbor 100.0.0.6 ebgp-multihop 255
neighbor 100.0.0.6 update-source Loopback1

! This works just fine...

---------------------------------------------------------------------

I managed to get all these peering working fine by using physical interfaces
instead of loopbacks whenever I had issues. But the fact that I was not able
to have peering working through loopbacks bugs me and that is why I am
asking for help....and the fact that the Task requires R6 to use loopbacks
when peering with R7 suggests there is a catch on this set up...so I better
clarify this. By the way, the underlying TCP connections work fine.

 

Thanks

 

Bauke

 

 

  _____  

The new Internet ExplorerR 8 - Faster, safer, easier. Optimized for Yahoo!
<http://downloads.yahoo.com/ca/internetexplorer/> Get it Now for Free! 

No virus found in this incoming message.
Checked by AVG - www.avg.com
Version: 8.5.364 / Virus Database: 270.12.65/2171 - Release Date: 06/15/09
05:54:00

Reply via email to