Network problem

[montee]

I have a server,with a 24 port 3com switch, with 25 client pcs(all running winxp pro) connecting to this server
my problem is that client pcs occasionally lose connection to this serve,but they can access all other network resource,if you chk network neighbourhood from the server you will not see any other pc only the problem server will be displayed, but if i off/on the switch everything will now be ok,the clients can now connect to this particular server,
I thought this might be a cable problem so i changed the servers network cable connecting the server straight to the switch but the problem still happens occasionally,does any body have a suggestions on why this happens and how it can be rectified.

 

[BigShyBear]

There are a large number of possibilities based on the information you have provided. What exactly are you turning off/on? Is it the server or the switch?
Server - network card. Could be a bad network card, a desktop network card that cannot handle the amount of traffic a server needs to handle, a bad network card driver set, or a driver set that can't handle the throughput.
I would throw a different network card in the server, preferably an Intel or a 3Com, and get the newest driver set for the card. In any event, update the drivers for the network card. The server network card driver set is the second most likely cause of the problem, followed by problems with the network card.
Cable - it could still be the cable. I've had this happen to me, I replaced one bad cable with another bad cable. Try a new premanufactured cable, preferably a Cat 5e or a Cat 6 cable. Based on the symptoms you describe this is not likely, but it's a fast fix.
Switch - This is the most likely source of the problem. A number of things may be happening. 1. the bank of ports you are plugging the server into may be failing. 2. the software in the switch cannot handle the traffic volume. Trying moving the cable to a different bank and see if the problem continues. Check to see if this is really a switch and not a hub. Check for updated code for the switch.
Many switches have either management software available for them, or built in web servers. See if you can get one or the other working so you can get any information from the switch on the port the server is plugged into.
By my count you have 26 devices plugged into a 24 port switch ("I have a server,with a 24 port 3com switch, with 25 client pcs"). Are you cascading into another switch?, does your switch have 2 gigabit ports you are plugging into?
And what version of Windows Server are you running on the server?

 

[montee]

sorry about the misinformation i have 15 client pcs not 25 and my server is running win2000 pro
I have a switch a 3com super stack and am not cascading , Thnx man i will post an update if it works, this is a very good site guys keep it up

 

[WhoKilledKenny]

Is that a typo (my server is running win2000 pro)? If you are running win2kpro as your server it will allow only 10 active connections. If you are running win2k server you do not have this limitation.

 

[montee]

bigshybear
The problem was from the network card even though it had the latest driver set.
I have 2 network cards 1 for the lan and the other for the voip, what i did was to swap IP addresses btw the lan and the voip card and the clients can now connect without my having to turn my switch off & on (do you have any idea why doing this enables the client to connect, do u think it has anything to do wit the speed at which the card runs until it is forced to run at 100mbps?) But i still had to turn my switch off & on before my users could use the voip????? im really puzzled once the faulty card starts working it continues,the problem is getting it to work in the morning the question now is wat could be wrong wit it?,why does it behave like this? im going to change the card but i would love to find the cause of this .
Thnx for the assistance

 

[BigShyBear]

We don't have enough information to identify the exact cause of the problem, particularly since we still still don't have all the information on your network setup. But if swapping out the network card fixes VOIP, I'd throw the old network card away (the network card you removed and replaced).