Hi all,
I have searched a lot in google and did practicals on dynamips too
but still I did not come to any solid conclusion when holdown timer starts.
so many articles posted on google and all are contradictory to each other.
some articles say
1) holdown timer starts when the update is received for the route with a
higher metric (<=16) from the same neighbor and router starts the holdown
timer...during holdown timer router do not accept same route from any other
router but can accept the route from same neihbor if the metric is lower.
and durinh holdown forwarding of packets keep going on.
----- but this is not the case that I see in dynamips..I increase the
metric with offset list and all routers immedialty accept the route with new
higher metric
some other articles say
2) when a router does not receive a route for default 180 secs, only then
holdown timer starts....
------in order to check this, I used *times basic 10 30 60 90 on all
routers. So 30 is invalid timer after which route should be in holdown for
30 more secs.*
**
But immedialy if timer crosses 30 secs... i see in show ip route <> that
says holdown 0 secs left..even still there is 30 secs to go..and route
disappears..after it reaches 34-35 secs
why this behaviour is so ?.. could anyone please clear this when holdown
starts and explain the full mechanism ?
thanks
--
Taqdir Singh
+91 -9911709496
+91 -8010415988
"do today what others wont so you can live tomorrow as others cant"
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