Bottlenecks across WAN

[justjasb]

Our IT dept. switched out the switches in the data closet. After the switches were changed, there was a drastic slowdown in the AutoCAD performance due to the network lag times. We run around 25 seats of (standalone) AutoCAD 2004/2006 working on files that sit on a novell cluster server.

Any solution to enhance the performance of the AutoCAD files across the WAN?

Your suggestions will be greatly appreciated.

Cheers,
Jason

[HuFlungDung]

From what I've heard, a switch is not the best device to use on an ethernet because of data collisions, since all data attempts to be sent out all ports.
A router does a better job of sending data down only the wire that needs it.

[GdeColigny]

Originally Posted by justjasb Our IT dept. switched out the switches in the data closet. After the switches were changed, there was a drastic slowdown in the AutoCAD performance due to the network lag times. We run around 25 seats of (standalone) AutoCAD 2004/2006 working on files that sit on a novell cluster server. Any solution to enhance the performance of the AutoCAD files across the WAN? Your suggestions will be greatly appreciated. Cheers, Jason

Contact the network team. There is certainly a screw up in the switch configuration (these things are not always plug and play). Have numbers ready, (like before it was taking xxx second to open, now it's zzz). Describe the problem you have (only your side), don't try to suggest them anything, don't even mention network lag time -because I don't think you use it as it really means in networking terms, and it might be more a collision problem (don't speak about collision)-, don't say "your switch are bad, your setup is bad" or else.

Insist on the fact that it make work difficult to impossible.
Prepare a bottle of -something they might like- if it's fixed fast, give them the bottle, if they have to wait for more technical assistance from the switch maker, offer them a glass, promise them the rest of the bottle for when it's fixed. If they don't care, break the bottle on their skull.

Any fix on the autocad side is more likely to be like a cast on a wooden leg...

[GdeColigny]

Originally Posted by HuFlungDung From what I've heard, a switch is not the best device to use on an ethernet because of data collisions, since all data attempts to be sent out all ports. A router does a better job of sending data down only the wire that needs it.

Don't take it bad. But you have no clue whatsoever about what you are talking.

Switch and hubs forward network packet without understanding their content (for switches just the hardware address of the device supposed to be reached). Routeur are all about forwarding network packet according to the protocol they use to encapsulate the data (higher OSI level).

If their is a Wan involved you have the sheme:

workstation(s)->switch(es)->routeur->INTERNET(OR any other WAN, leased line, sat uplink)->routeur->switch(es)->Novel_server

[justjasb]

Hi,

Thanks for the reply.
Our switch engineer says the only change he made was that, that he eliminated
broadcasting and/or multicasting over the network.

Do you know whether AutoCAD requires this, to run efficiently, on a large corporate network or not?

The intermittent, random lag times while using AutoCAD are quite frustrating to the CAD users here.

Thanks

[GdeColigny]

Originally Posted by justjasb Hi, Thanks for the reply. Our switch engineer says the only change he made was that, that he eliminated broadcasting and/or multicasting over the network. Do you know whether AutoCAD requires this, to run efficiently, on a large corporate network or not? The intermittent, random lag times while using AutoCAD are quite frustrating to the CAD users here. Thanks

I don't know the specifics for Autocad use over a wan link Nothing is really "turn-key" solution in the networking world.
The dumbest advice I can give is, ask them if they can revert to a previous config in order to test if autocad behave better.

BE EXTRA CAREFULL, if it's only lag on working with file, it's annoying, but no more... BUT, the -random- part scare me a little. I fear that file corruption may occur (destroying your project document, making them unreadable). I don't know what recourses you have. But if you have a backup admin/sysadmin ask him to keep carefully version of your projects dating from before the network change.

***Before this, it can be necessary to try a copy of a big document (big compared to the speed of the link) to see if copy take a normal time, the best is to test it with FTP client/server as they tend to advertise precisely the speed of the transfer and the time remaining before completion. Is that completion time vary greatly or keep getting longer there is a problem on the network side.***

All the part between stars is basic network troubleshooting... avoid telling them, they certainly know and won't be happy if they think you want to teach them their job...

[justjasb]

Well, somebody suggested me to try enable/disable Digital Signature. After digging up on the matter, I tried that too. But in vain

The system still lags every 10-20 minutes. I have tried these on some of the other machines but it has not seemed to help them either.
The network lag seems to be only affecting the systems that have AutoCAD installed on them.

Any help !!

[WayneHill]

Check the switch manufacturer for the latest firmware update.

[damienrange]

We had a similar problem and this was caused by certain AutoCAD files (dll files) being located on our main server. Each time certain commands required this input it would cause a lapse as the PC was looking back at the main server. Our IT guys managed to solve the problem, will let you know.

Hope it might help.

[justjasb]

We are very eager to know about the solution that your IT guys used to solve this issue. It might help us also.

Thanks

[damienrange]

Our IT guys have deployed the appliance from Riverbed. They look much happier with the performance they are experiencing with it. With the Steelhead appliances and Steelhead Mobile, our employees recognized the difference immediately.

In addition, employees who were previously unable to effectively work from home when working on a tight deadline can now access files and information just as if they were in the office.

[garyparker84]

Take a look at the Riverbed's Steelhead products. One of our partners implemented Riverbed Steelheads some time back. They told that the product was incredibly simple to install, and demonstrated efficient bandwidth results and latency improvements.

Since you are particularly working with AutoCAD files, there is one performance brief available which clearly exhibits the level of performance for these file transfers. Click the link below :

http://www.riverbed.com/docs/Perform...ed-AutoCAD.pdf