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thtan56

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3com switches reboot every few minutes

3 of my office 3com switches, 48-port 3c17302, reboot every few minutes (such as 3 to 5).
These cause the servers and workstations to have 'unplugged' and 'plugged' status for the network adaptors (in Windows environments)

A few 24-port switches don't seem to have this problem.

Suspecting overloaded and transferred a few points to a number of unmanaged hubs.
The frequency has reduced but the problem still exist.

The stacked switches were then separated and connected to the cisco 3550 into a collapse backbone setup.

According to 3com engineer, after intending to return the equipments that were still under warranty, i needed to upgrade my firmware from version 2.02 to 2.10.
I managed to download and upgrade the firmware for one of the switches.
I hope to see that result on next Monday on whether the switch still reboot after the patch.

Any recommendation.
I am comtemplating to replace the 3com switch to 3com hub or get new cisco switches.



 
Avatar of JRaster
JRaster
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I have 12 3com switches and have no issues.  You can have problems with cisco switches too.  
My last job I replaced 3 cisco switches in a year.  
If your primary network is switched by 3com, stick with it.  One bad switch is not uncommon.  
With any network that depends on switches or hubs through out, keep a backup on hand.  =)

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Avatar of jhilving
jhilving

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Hi, there

If its a managed switch use a serial interface Null Modem cabel rs232, log onto the switch do a reboot of the switch does it compleete all test and the mem test. if not faulty item.
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PennGwyn

A couple of months ago, Cisco provided a software upgrade for a number of its switches that addressed a problem which, in certain configurations, could have allowed a malicious person to make those models reboot unnecessarily.  I do not know if 3com had the same problem (it's possible, but I can't guess how likely), but if so then perhaps the firmware upgrade fixes it.

Sounds almost like the broadcast from the server (DNS, DHCP, etc.) is causing the reboots.  Check how often the server/client lists are updated.  If you can extend the time to say 15 minutes and the reboots also start around that time (and not 3-5 minutes) then you will at least know what signals are causing the reboot.
Sorry, I forgot to mention - I had a similar problem with computers suddenly coming ON LINE (Booting from a shut-down mode) every 30 minutes.  A change in the bios solved the computer problem!
I wonder if its just one bad switch.  Assuming the switches are uplinked, a problem with 1 switch (not a failure) may be overloading the other switches.  Do you have enough open ports to completely eliminate the switches one at a time?
Avatar of thtan56

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New information on the above problem.

When upgrading the software to version 2.10 from 2.02, the re-boot did not occur but a new problem happened.

I was not able to ping the switch.
Using any network discovery program was not able to recognise the switch.
When connecting to the console using hyperterminal, the response from the switch was very slow.

After reporting the incident to 3com helpdesk, I ask to use the same suggestion from jhilving i.e took the switch offline.
I was able to check the switch with that.
After getting the antivirus expert to clean the servers for virus, the switches were more responsive.

In summary, the reboot happened to all the 3com switches (8 in total).
Look like, the switches were not response to any ping or web management when they were overloaded i.e. could not be managed at all