RE: Reachibility Issue.

Check routing tables on both devices, if you're redistributing and expecting a route from one protocol to show up in another, make sure it's shows up in the routing table as route for the originating routing protocol.
Check your entire layer2 path for the VLAN with issues, make sure it's not being pruned and exists in the VLAN database, show int trunk etc...
Probably a good time for debug ip routing and watching for your disappearing route.
For me though, the number one issue here is typically an interface that's not being redistributed properly, it's usually very easy to spot with your ping script and involves adding another network statement or including an interface in a route-map. I approach the lab fairly linearly, so I work through all the layer2 reachability issues as my first step and verify I can ping all directly connected neighbors. Then as each layer3 routing protocol is added, I typically ping a few key devices for verification there as well. By the time I get to my ping script, it's usually just a short cleanup or a few modifications of AD.

-ryan

-----Original Message-----
From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of sajid mavani
Sent: Saturday, September 12, 2009 3:38 AM
To: ccielab_at_groupstudy.com certification
Cc: sajidmavani_at_gmail.com
Subject: Reachibility Issue.

Hello Seniors,

I had a query if in case you are not able to ping any of your routers or
Backbone interfaces what is the best possible troubleshooting steps.

As per my understanding I would follow the following steps.

1) sh ip int b -- check the line protocol
2) check duplex settings
3) trace route check .
4) check for any access-list configured that would block ping reachibility.
5) check proper access vlan passed in the given interface
6) ?
7) ?
8) ?
9) ?

Also if possible let me know what would be the best approach to
troubleshoot any layer 2 & Layer 3 related problems if possible.

Please let me know what would be the best approach, kindly reply to my query
as per your convenience

Have a pleasant day!!!

Regards

Sajid .

Blogs and organic groups at http://www.ccie.net
Received on Sat Sep 12 2009 - 10:43:10 ART