ASR1K BGP Local Preference Changes

[Rob Sciarrino]

I'm in the process of migrating traffic from one provider to another. 

Currently, Provider A is set with a Local Pref of 200 and Provider B with a Local Pref of 100.

Do BGP Local Preference changes take place immediately, over time, or does clear ip bgp soft need to be performed for anything to take effect?

My ultimate plan is to shutdown Provider B and have all traffic on Provider A.  

[Giuseppe Larosa · Accepted solution]

Hello @Rob Sciarrino ,

>> Do BGP Local Preference changes take place immediately, over time, or does clear ip bgp soft need to be performed for anything to take effect?

BGP local preference happens immediately on the node that you configure it on.

However, this BGP attribute is sent only to iBGP neighbors in the same AS ( from this the name local preference)

So for sure you don't need to clear ip bgp soft the eBGP sessions.

If you have multiple BGP routers in your AS it can take some time before the change is propagated everywhere.

From the point of view of eBGP peers nothing changes.

Hope to help

Giuseppe