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Network keeps going down – seems to be caused by a plotter – help!

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I am running a small business network, about 15 pcs all running XP. Our server is a Net Integrator, which is a Canadian linux-based all-in-one product, now owned by IBM/Lotus. The server is our file server, DHCP server, overall gateway. It works exceptionally well.

The general setup is that all devices are plugged into network outlets, the cables of which run back to a patch panel in our server room. Each plug is then patched to a plug on a 24-port HP procurve switch. The server is plugged into one of the ports as well.

The problem we’ve been having is that our network goes down sporadically, occasionally, without any hardware or software change. One minute it’s there, the next, it’s not.

Through troubleshooting, I have made some configuration changes, and identified some parts of the network that weren’t set up right. However, I have now got the problem seemingly isolated to one device on the network.

It is a plotter we use for engineering drawings. It is a networked plotter, a Canon iFP710. While the whole network runs off the DHCP server, the plotter is assigned a static IP address. It has a built in network card. This has worked well for us for almost a year. However, today it seems to be the cause of a problem. And perhaps it has always been the cause of this sporadic problem. When I plug it into the switch, the whole network goes down. When I unplug it and re-start the switch, the network comes back, generally problem-free. I have replaced the cable from the plotter to the wall, and also from the patch panel to the switch.

Anybody have any ideas for me, or is there more info I could provide that will help diagnose this problem?

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Clarifications

In reply to Network keeps going down – seems to be caused by a plotter – help!

Clarifications

You say the plotter has a static IP…

In reply to Network keeps going down – seems to be caused by a plotter – help!

You’re not getting a conflict with a DHCP one being assigned somewhere are you? Can you change the plotter to an IP outside what the DHCP dishes out?

get a simple ethernet hub and an old laptop.

In reply to Network keeps going down – seems to be caused by a plotter – help!

Install the free WireShark protocol analyzer on the laptop.

Plug the plotter and your Wireshark PC into the hub, and plug the hub into a port on the LAN.

With Wireshark you can observe every packet going to/from the LAN.

Chances are that the network interface card on the plotter has gone wacko and is spewing out 100,000 packets per second, which you should be able to observe with Wireshark.

http://www.wireshark.org/

a thought

In reply to Network keeps going down – seems to be caused by a plotter – help!

The card could be “going out”, causing a broadcast storm… Hence, the network goes down… I would packet sniff that switch, or do some sort of monitoring on it to see if that is the case.

You could also research to find out if there is any firmware updates out there..

a few years back, from what I remember LA internation air port’s network went down due to a faulty NIC card that caused a broadcast storm…

Also in personal experience, I recently was dealing with a server that was kinda DOSing itself… the RAC card (web login, to work on the server if a NIC goes out) went haywire, slammed the server with bogus account requests, filled up the event logs with crap… which caused the server to go MIA… Firmware fixed that…

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