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New Member

3550 connect High Schools

WE have five High Schools connected over WAN via 3550's.

The Network OS is Novell 5.1 pure IP.

We are have trouble communicating UDP.

Clients need to communicate across WAN to DIRECTORY AGENT.

Upgrading to NW6 migration also needs good UDP communications.

How do I configure and ensure that the TCP and UDP ports used by Novell are open?

UDP and TCP port 427, TCP 524,




Re: 3550 connect High Schools

Unless you configure an access-list blocking TCP or UDP ports on the 3550s and any intermediate routers, all the protocols and ports are by default allowed. You do not have to do anything to configure them to be allowed.


Re: 3550 connect High Schools

If you are already having trouble it might be UDP broadcasts that are getting dropped. The router will drop UDP broadcasts unless you configure an IP HELPER-ADDRESS x.x.x.x on the interface where the broadcasts are received. It gets specific as to the ports it forwards. Check it out in the cco docs if it sounds relevent.

Do you have IP multicasting turned on? It was necessary for Novell 5.1 here.

BTW: How does a 3550 do WAN links?

New Member

Re: 3550 connect High Schools

We have the 3550 configured with EIGRP (Routering Protocols).

I will check out the IP HELPER-ADDRESS info.

We are have major problems migrating to NW6 and I think the problem is due to poor UDP communications between Server migration agents.