Duplicate IP's on the Network

[Minus Human]

HI

Hope you guys can help,

we had a strange problem last night. All of our Netware servers crashed last night with an error that a "duplicate IP Address"

After rebooting the servers and all switches the problem was solved. But our concern is why would this happen? None of our Microsoft Servers gave an error.

Anybody have this before? It happened around 3'oclock in the morning. I'm concerned it could be a virus of somekind?

Any help?

Thanks

Minus Human

[texas_leaguer]

What brand of switches, dell? If so, STP (Spanning Tree Protocol) has been known to cause this issue; I've had it occur on my corporate network a handful of times.

[Minus Human]

They're nortel 450 switches and a couple of 470 switches. last night we had the same problem.we've changed the spanning tree option from fast learning to normal learning.

we set up port mirroring on a port that was pushing through a high rate of traffic (99%) 85% of this traffic was UDP traffic.

But i can't find anything that would create such a larage amount of UDP traffic?

Any suggestions.

Minus HUman