We have started to exp an unusual problem where every 5 (ish) hours 2
NetWare servers appear to die. On the console the servers are showing no
problems except they cannot communicate with anything else.

Pings show no response, network based services cannot communicate (even
with services on the same server) and no one can access the servers across
the network.

Reinitialise the comms does not work only a reboot. I havenow found that
if I unload named.nlm the server starts to work again.

We are running NetWare 5.1sp8 and NetWare 6sp5e.

Any ideas please?