BGP neighbor/configuration testing

Eric A Louie elouie at
Wed Nov 20 19:53:54 UTC 2013

Scenario: a regional ISP preparing to cutover to a new upstream BGP provider at one of my POPs.  Want minimal or no network disruption, and want to ensure everything is ready to go prior to the cutover.

 I'm planning to use the following order of operations:
1. Establish IP connectivity to the new ISP (already done)
2. Configure my BGP router and shutdown the new neighbor (ISP says their side is already configured and ready)
3. During the maintenance window for this change, activate the new BGP connection (remove neighbor shutdown)
4. Do the appropriate tests (sh bgp nei, login to my upstream's route server and check route advertisements, sign in to looking glass and/or route servers from other providers to see if my routes from the new ISP are being advertised, and I'm open to any other tests)
5. Turn down the old connection (neighbor shutdown)
6. Watch the old connection get removed from route servers/looking glasses from step 4

A. Does that order make sense or does it need some tweaking, additions, or "other"?

B. I'd like to test the new upstream BGP configuration without passing traffic to and through it.  What can I do (if anything) on my configuration end to put up the BGP configuration, establish a neighbor connection, and NOT actually pass any traffic through it?  After putting my configuration up, I'd like to do a show bgp nei advertised-routes to ensure my routes are going out, and then shut the neighbor down until the cutover.

thanks for your input

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