Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements

Attention: The Community will be in read-only mode on 12/14/2017 from 12:00 am pacific to 11:30 am.

During this time you will only be able to see content. Other interactions such as posting, replying to questions, or marking content as helpful will be disabled for few hours.

We apologize for the inconvenience while we perform important updates to the Community.

New Member

bgp dampening...

hi. which route the dampening process will suppress? is the route in the internal AS it self or route that exists in another AS that transit via our AS? would u please give a condition in the internet that flapping happen that bgp dampening helps... tx :)

2 REPLIES

Re: bgp dampening...

Hi,

The dampened routes are routes learned from external AS. Routes learned from external AS via iBGP is not dampened.

Flapping BGP routes cause an instability in the internet routing table and consume processing power in BGP routers as it tries to re-calculate a large number of route updates. For a large ISP/Carriers which allows AS transit, dampening is a must. For small data centre that doesn't allow AS transit, dampening is an option.

New Member

Re: bgp dampening...

ok tx but let me think.. Assume there is AS1 AS2 and AS3. as1 and as 3 has one bgp router, as 2 has two bgp routers. figure like (as1)<->(as2-as2)<->(as3). assume that connection from as1 to as2 is bad/flap. how router as2 on the right connecting to as3 know that as1 to as2(left) is bad so as2(right) will supresss that flapping route to as3. is there atrribute to let know the as2 on the left? please give understanding to me. tx very much :)

132
Views
0
Helpful
2
Replies
CreatePlease to create content