Severely slow connections

[cnull]

We have been having a problem with connection speeds to our Netware 5.1 SP3 server lately. This began about a month ago.
The symptoms are the following:
+only happens between the hours of 7:30AM - 8:30AM
+Extremely slow directory browsing
+ping test avg 140ms no packet loss(other times avg = <1ms)
+over 400 clients without access to drives during that time
+other netware servers do not have this problem
+connection to any other server or service durring this time is not a problem

I am fairly sure we have rulled out any processes local to the Netware server itself. In the kernal/processes there is nothing significant to report. Utilization stays at about 2-50%(very normal for us). No backups running at that time(we even unloaded anything to do with the backup client to make sure that it was not related). We uninstalled Symantec virus protection for a day to eliminate that. Packet receive buffers, Service processes, connections and open files all within acceptable limits. LRU sitting time well over a day.

I think that the problem is more likely a network connection problem(FYI: no errors in TCP or IPX stats) or a external process that is taking up all the bandwidth. Unfortunately that is where I have the least experience. Is there a tool that I can use like netstat or some sort of connection analyzer for netware? Any other suggestions?


Any help is much appreciated!!!

Chris

 

[marvhuffaker]

Quite honestly, 50% utilization is not normal. I am guessing that it is directly related to your problem. Even a very busy server shouldn't run more than 10% utilization, and even that is kinda high.

Is this a 2 processor server? Check this link so you can make sure you are reading the utilization correctly.

http://www.redjuju.com/resources/guides/multiprocessors/index.htm

What is the role of this server? What about updating the Service Pack? You should be at Service Pack 8. I've seen DS issues on NW5.1 cause utilization issues which may be resolved by the patch.

Marvin Huffaker, MCNE

http://www.redjuju.com

 

[cnull]

I guess I should clarify 50% utilization is not something we see often, just periodic spikes for no more than a couple of seconds at a time. I was just giving a total range. 90% of the time the utilization is below 10%, in fact it is usually ay 2-3%. And I would stress that there has not been any upgrades/changes to the server directly that I could say might have caused such a change in the performance. Also remember this only happens during the hours of 7:30AM to 8:30AM. Most of our employees are already signed on by 7AM.
I did however look at the web page that you linked to. The server contains two processors, but we are not running the multi-processor NLM. Back when this server was setup Netware either did not support it or we were not on the correct version. So in the console it only registers a single Processor. Since I have no reason to beleive that this is a problem local to the server I do not think that I want to apply the patch at this time. We are scheduled to upgrade to NW6.5 in November.
I am looking for a diagnosis first. That is why I am looking for a connection analyzer of some sort. I will make changes only after I can be sure that I know what the problem is.

Thanks for your input!

 

[marvhuffaker]

This is a good forum to get general guidance and recommendations, but it's difficult to solve a server problem based on general information. Much easier if you have error codes or whatever.

That said, you need to find out if it's a server process or a user process that's killing it. Not an easy task. You can use the portal

http://server:8008

to get quite a bit of information, or you can look at the threads in Monitor and see if you can pin anything to a specific NLM.

One thought is that your compression engine may be running, starting at 7:30 and then it goes for an hour. But since you have not done any maintenance on your server for about 5 years, I doubt you've done anything to change defaults either. Compression engine runs at midnight by default. You can check these settings in Monitor.

To expand on the patch issue.. and to make it clear, I am not a patch freak. But come on, you're 5 MAJOR patches behind. Good chance that a patch will go a long way here. And you could have applied SP8 in the time it took me to write this post, so I'm not sure where the hang up is on the patch.

Patch first, troubleshoot later. Help us help you.




Marvin Huffaker, MCNE

http://www.redjuju.com

 

[TheLad]

Marv does have several valid points there regarding patching and compression.

Also, if the server runs any virus scanning NLMs, check to ensure that a full server scan is not running daily. It might also be worth checking to see whether someone has a scheduled process that might be running every day between the times you state.

I presume your DS is healthy on this server (if it has replicas?)

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"Insert funny comment in here!"
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[cnull]

Well I finnally got some help from a network guy who was able to place a sniffer on the switch. The problem is due to a handfull of clients running a massive file copy process (at 7:30 to 8:30 every morning) that our GIS programmers put in place (they did not notify anyone outside of thier group). So once that was discovered we moved the files to a new location and tada!!! It is all back to normal.

Thanks for your help!
Chris

 

[marvhuffaker]

This is not related to your slowness, but you mention you will be upgrading to NW6.5 this fall. You should upgrade your service pack to SP8 before you try to upgrade or migrate to NW6.5. You should also update your DS version to the latest version..

If you are running DS version 7.x, you need to be on 7.62c(?) or latest one as posted on Novell's site. if you are on version 8, you should install eDir 8.7.3. It may be a good idea to get up to 8.7.3.8 regardless of whether you're on NDS7 or NDS8.

If you don't do this, you're probably going to have problems during the upgrade.

Marvin Huffaker, MCNE

http://www.redjuju.com