Network Bottleneck.

[WyzrdX]

Hello all.

I have been reading the site for a while and I figured this would be a good place to get answers.

I am a Systems Administrator for a Furniture Company and I am solely responsible for 5 locations accross the country. (Really Bytes Sometimes)

What I have at one location, our Corp HQ, is a very messy network. I will point out some parts of the system.

1. We have 2 Netwoks Independent of each other. 1 is our POS, the other is our Internet/ Data connection.

2. We have no Server on our Data. All are in multiple workgroups.

3. We have a Data Room where the T1 and Phone trunk come into the building. Here we have a Dual Wan Netgear Firewall Router.

4. We have a patch panel in the Data Room that feeds the rest of the store.

5. We have 6 RAN Shelves in the main part of the store. (Shleves on the posts that our data lines and phone lines run to. FYI) Each Ran Shelf has 2 switches. 1 for Data 1 for POS. All are in a star pattern connected directly to the Data Room.


OK This is where we have trouble. About 16 months ago we added an new wharehouse to the back of the store. In it included 2 new RAN Shelves to feed the back of the wharehouse and a new Customer Service Call Center.

The new RAN Shelves were daisy chained to the closest one in the store with a single wire. Meant to feed approx 25 connections.

Everything has been working fine until now. In the last 2 months, I can test speeds in the main store and get approx. 1250 to 1500 download and 1100 to 1400 up.

Back in the addition I get speeds of 460 down and 1150 up. I had traced down the issue to the RAN shelf outside of Customer Service. When I could not determine anything at that point I replaced the 2 existing 24 port switches with a 48 port managed switch.

After adding that I saw the speeds jump back up to normal. The the problem hit.

One of the CSR agents asked me how long the network would be down. In my rush to get it all hooked back up I had left them disconnected.

They are connected via a single wire from the RAN shelf to a switch inside the call center. If they are disconnected speeds are normal, if they are connected speeds drop. But only if they are in use.

I am in here today before anyone is in and the speeds are 1395 down and 1361 up. When I left there were only 5 people connected and speeds were 420 down and 1157 up. And it doesnt matter which 5.

Can anyone tell me what can be going on or if I can get a tool to monitor internal data?

How can I pinpoint the bottleneck? This is frustrating but I am hoping the SNB Community can help with this one.

Thanks all.

 

[thiggins]

What are the speed numbers you are quoting measuring? Internet speed? Switch to switch speed?

What is happening with the port lights on the "problem" connection (the one that slows things down)? Are they flashing wildly? Have you ensured that there aren't two connections between switches that could be causing broadcast storms?

The managed switch should have port mirroring. So you should be able to mirror traffic on the problem port to a port where you have a system that has Wireshark loaded on it. Then you can do a traffic trace and see what is happening.

 

[WyzrdX]

What are the speed numbers you are quoting measuring? Internet speed? Switch to switch speed?

What is happening with the port lights on the "problem" connection (the one that slows things down)? Are they flashing wildly? Have you ensured that there aren't two connections between switches that could be causing broadcast storms?

The managed switch should have port mirroring. So you should be able to mirror traffic on the problem port to a port where you have a system that has Wireshark loaded on it. Then you can do a traffic trace and see what is happening.

The Speed being measured is Internet Speed. As for the lights they are flashing normally.

I have never heard of wire shark but I will chack it out.

I have narrowed it down to a wireless access point. When it is disconnected I am getting near normal speed but with it connected speeds are cut 1/3.

If there is any more information needed I will post it if I have it or I will try to get it.

Thanks for the reply.

 

[thiggins]

My guess is that there is may be a computer that is connected both wired and wireless on the problem switch.