Link to home
Start Free TrialLog in
Avatar of lenivan
lenivan

asked on

sporadic network drops

The problem I'm having is that several times a day, my workstations drop from the network. This appears to be completely sporadic and nothing out of the ordinary is running when this occurs. Users who are connected to my Exchange 2003 server through Outlook get a delay in send/recieve and then it tells them the Exchange server is unavailable. They reboot and all is fine.

This doesn't only happen with my email server. It happens with my flie server and my domain controller as well. What could be the cause of this? I ran a packet analyzer and couldn't find anything out of the ordinary. All workstations are identical running XP.
Avatar of RDAdams
RDAdams
Flag of United States of America image

Are they running on a switch or hub?  Wireless or wired?
Avatar of lenivan
lenivan

ASKER

They are wired and connected to jacks in the wall which connect out to managed switches. The managed switches are connect to a backbone switch which all the servers and firewall are plugged into.
ASKER CERTIFIED SOLUTION
Avatar of NetAdmin2436
NetAdmin2436
Flag of United States of America image

Link to home
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
Start Free Trial
Avatar of lenivan

ASKER

No, they don't all drop at the sime time. Seems completely random.

When they drop from the network, their IP address is what it should be. No issues there. I've checked every router, switch and hub and disabled DHCP on them (unless there's a rouge device that I can't find).

I flushed the DNS before, but did it again just now just to make sure. The problem continues to occur.

Anything else I can try or look for?
Hmmm...Is every single computer droping? or just some? Are they all on one particular switch?

I've seen a bad cable cause this type of behavior, but if it's happening to many or all computers i'd tend to think it's something else. But check the uplink cables from switch to switch for sure and cables to servers. This is where a good cable tester is handy to have around.

You can check the speed and duplex on the switches and NIC's. Normally Auto should do, but you can force 100mb full or half and see if it helps. They must match for each NIC to respected port on the switch.

Otherwise it might be time to start disabling client/server firewalls, antivirus/antispyware software. Disabling the service ensures it gets disabled.

Tried rebooting switches/servers?
Avatar of lenivan

ASKER

we've got 200 computer, but only about half are dropping. They are all connected to different managed switches, but all the switches are connected to 1 backbone switch. The servers are connected directly to the backbone switch.

All the switches are 5 years old and I will be replacing the backbone switch in the next day or two. I guess it could be a bad cable. When I replaced the backbone switch, I will replace the Cat5e cables on all the switches with new Cat6 cables.

Hope this will make a difference. Any other suggestions?
I will report my findings after the hardware replacement.