SBS 4.5 intermittent client logon failure(s)

[Enkhidu]

I have a SBS 4.5 box with 98, 2K, and XP clients and have just recently run into some sort of logon problem:

Because of some hardware limitations, we ended up having to put a tape drive in one of the 2K clients and doing some backups across the network. Up until just a few weeks ago, this worked - albeit slowly - without a hitch. However, it now will intermittently lose the connection with the server during a nightly backup. Further, the following morning after the backup fails, the server will not respond to any client request and will not allow logons of any sort. The server, however, can still ping client stations and can still reach outside the network IPs. Rebooting the server restores all connectivity and allows logons.

I have already tried replacing the server's NIC and network cable. I then figured it might be a problem with the NETLOGON service and tried a stop and restart of that service; however, this did not work.

What am I missing?

 

[karmic]

Have you checked the event viewer for errors or warnings?

Curious, when were the xp workstations added to your network? I have seen times where windows xp takes control of the browsing service from windows NT. When the XP workstations are shut down, the NT server sometimes cannot cope.

Try disabling the computer browser service on the XP/2000 workstations, reboot the server and let it sit overnight.
Make sure the computer browser is running on the NT server.

Good luck

~ K.I.S.S - Don't make it any more complex than it has to be ~

 

[Enkhidu]

Actually, I had that problem earlier with this network, and ended up turning off the browser service for all the clients. When this problem first arose, I thought it might be a problem of the NT server releasing the master browser role for some reason (possibly because of a intermittent network connection drop?) and re-ennabled a Windows 2K Pro client to take that role when necessary. However, the problem arose in both configurations, so I'm back where I started.

 

[DG659]

do a virus scan sounds like your getting something like a smurf attack.

i usually use symantecs online scanner if i think my internal VS has be comprimised (it dosent fix it but it tell you where to look to get the problem sorted).

http://www.symantec.com/cgi-bin/securitycheck.cgi