OSPF Query

Archived from groups: comp.dcom.lans.ethernet (More info?)

Not sure if this is the right newsgroup, but here goes.

Have a small network, only five routers all running OSPF in a single area. Two
of the routers are connected via WAN links that have aggregate speeds of about
45 Mbit/s.

The problem I have is that during very heavy traffic periods, we loose the
remote routers and we cannot recover them unless we bring the links completey
down and then re-open them. Ran Etherreal going into the WAN links and have
seen the traffic hitting 45Mbit/s. I have confirmed this also by performing
very large "pings" 64K bytes and the links go down straight away.

I have checked using "show ospf" commands that the routes learned across the
WAN links have gone.

What I don't understand is that if I physically disconnect the WAN links we
obviously loose the remote sites, but if I restore them everything comes back
after a few moments. It is only during the very high traffic "peaks" that we
loose the links completely.

Has anybody seen or had any similar problems, Cisco Tech Support were baffled
as well.


Regards

Nicki

Archived from groups: comp.dcom.lans.ethernet (More info?)

> NICKTTI <nicktti@aol.com> wrote:
> > Not sure if this is the right newsgroup, but here goes.

It's not. comp.dcom.sys.cisco is better.

[snip]
> > after a few moments. It is only during the very high traffic "peaks" that we
> > loose the links completely.
> > Has anybody seen or had any similar problems, Cisco Tech Support were baffled
> > as well.

You're dropping OSPF hello's because they are being washed out in the noise.
What type of queuing do you have?


In article <ca4ln1$1b2n$6@nyheter.ipsec.se>, phn@icke-reklam.ipsec.nu
says...
> Things to try :
> Reduce buffers available to normal traffic, prioritize OSPF or create
> static routes across the WAN links. Switch to EIGRP if possible.

I don't see how moving to EIGRP would help. It's hello's would time out
just as well.


--

hsb

"Somehow I imagined this experience would be more rewarding" Calvin
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