We've been running with the RIPE specified values on BGP dampening for a
while now. However - I noticed an oddity today when debugging zebra.
A route which was flapping was getting to its supress value, but never
going above it. This meant the route was withdrawn but almost immediately
re-instated with no hold down. It turns out that this is because we had the
supress value as a multiple of the half life.
We had:
route-map graded-flap-damping permit 20
match ip address prefix-list min24
set damp 30 750 3000 60
This caused oscillations inside our mesh - because the route was never
getting held down.
Once we changed it to
route-map graded-flap-damping permit 20
match ip address prefix-list min24
set damp 30 750 3001 60
Then the route got held down properly.
Is this a bug in our understanding? or the code. I guess that as RIPE
specify this - there will be lots of people using it.
Rick
This archive was generated by hypermail 2b29 : Sun Aug 04 2002 - 04:12:19 EDT