Network slowdown -- weird problem that just started

[GCS]

Well I need some help trying to narrow down and solve this problem so bear with me a min while explain what's going on ...

For 20 years we have had a network running in our building .. simple peer - peer network nothing fancy.

Up until recently we never really had any trouble with it at all. About 2 months ago we got all new computers (predone dual core X2s all the same from HP -- 9 machines total + one server also a dual core but built here with different components).

Things seemed fine and no problems that I am aware of. Within a week of getting the sytems I had Kaspersky Internet Security installed on all machines. About a month ago we started having SERIOUS network slowdown issues. Examples below

Loading of simple MS Word files from the server would take 5-10mins instead of 2 seconds.

Loading of certain programs from the server (our tax and accounting software runs via a network install over the server ALL other software runs locally) that used to take 5 seconds might now take 10-15 mins.

Transferring a small fil 100mb or so might have only been a few seconds now can take 30 mins.

This issue is VERY RANDOM. 1 or 2 computers on the network may have this issue but the others act normal. Then the next day the 1 or 2 systems previously affected now are fine.

Also often the slowdown problem can be eliminated by rebooting the affected computers several times (sometimes 5 or 6 times).

I have tried everything my feeble skills can think of including all of the following:

1. Rebooting the server when the slowdowns occur -- gives no help
2. Replaced all NICs with new ones - no help
3. Installed a new switch -- seemed to help and then a day later we were back to the same problems
4. Rebuilt the entire server with all new parts (motherboard, CPU, HDDs, NIC, Power supply etc).

Folks I am at a complete loss here and have no clue what to do but performance is so bad now that I have people waiting on the damn computers vs. actually working. Any help you guys can provide would be terrific.

Hardware/Setup notes

All computers are the same and have the same NICs installed (Intel 10/100/1000 PCI NICs).

NICs are all set to autonegotiate. I have tried hard setting them and that has no bearing on the performance

All wiring is standard cat5 copper wiring and is in tact as much as I can tell

Server is a 3800 X2 running 4 SATA drives (7200rpm Seagates). With the exception of tax and accounting software that runs from the server it is just for data storage and files are accessed from it.

All workstations are running windows XP pro with all the latest updates.

All workstations are running (server as well) Kaspersky Internet Security v 6.0 with all the latest updates.

Norton Utilites is installed on all workstations as well (but not Norton AV or anything else).

Workstations have background programs running other than Norton and Kaspersky

Network is a simple peer to peer Workgroup.


PLEASE HELP!!

Thanks in advance

Greg

 

[ojai00]

You mentioned that everything seemed fine before you installed Kapersky. A month afterwards, you started experiencing network problems. Have you tried getting rid of Kapersky to see if it helps performance? After all, it is an AOL product

Make sure to scan all the computers to make sure they're not infected as well.

 

[GCS]

Originally posted by: ojai00
You mentioned that everything seemed fine before you installed Kapersky. A month afterwards, you started experiencing network problems. Have you tried getting rid of Kapersky to see if it helps performance? After all, it is an AOL product

Make sure to scan all the computers to make sure they're not infected as well.

I am not convinced that Kaspersky is the cause but I am also not convinced it isn't.

All computers are scanned nightly for viruses and drives defragged every other Friday night.

We have disable Kaspersky on affected systems and sometimes it peps the systems right up but an hour later (yes KIS is still disabled) they go back to being slow.

Basically I just cannot pin down the cause.

When we ran NAV (did for many years) we ran slow quite often but never like this and I KNEW it was NAV because it is such a resource hog. When we switched to KIS programs that would take 5-6 mins too load (our tax software) would load in about a minute now. Thus the switch from NAV to KIS.

Greg

 

[ojai00]

Have you also checked the NIC settings on the old computer to see if they were forced to a certain speed (i.e 100/Full Duplex)? If they were, your current computers might be running on automatic speed detection, which can cause slowdowns when transferring files, etc. Verify that the NIC speed settings match the settings set for the switch/network.

 

[GCS]

Everything was set to autonegotiate on the old computers and the new ones are set the same.

I have tried to manual set them as well and it seems to have no affect on the slowdown issues.

Greg

 

[nweaver]

this is one of 2 things, either a slowdown of the server itself (taking a long time to process requets) or a duplex mismatch with the server/switch. This sounds like a classic duplex mismatch

 

[GCS]

Originally posted by: nweaver
this is one of 2 things, either a slowdown of the server itself (taking a long time to process requets) or a duplex mismatch with the server/switch. This sounds like a classic duplex mismatch

Ok if this is the case and I have gone and "hard set" all computers to the exact same speed .. say 1000 full duplex etc. Should this resolve the problem??

The switch (a 24 port Trendnet) shows we are all running at gigabit speeds.

Greg

 

[manilapoo]

You should familiarize yourself with Wireshark (formerly known as Ethereal).

If your switch can do port spanning or port mirroring you can at least see what's going on at a packet level. If your switch is not capable of this you can run it locally on each machine that has the slowdown issue.

Also, you might want to look into the event logs of the clients and server for warnings and errors.

 

[GCS]

Just went through and set all the computers and the server to FORCE 100 Full duplex (there was no choice to go with 1000 at all even though this are all 10/100/1000 NICs). Rebooted all machines including the server.

The slowdown is still there on some machines.

**EDIT: Things are actually much worse. Basically no one can get anything to load up at all.

I have switched back to autonegotiate and things are much better. Still slowdown issues on 2 machines and all the rebooting in the world doesn't seem to help.

Greg