Router killing modules?

xenodamus

I think I have a serial killer 2620 on my hands, but I don't have a ton of hardware experience and would like the opinion of others. Here's the story:

I bought a 2620 with an NM-4A/S and WIC-1T for a good price on eBay. I get the thing in the mail and power it up. One ethernet port is dead and the NM-4A/S causes the router to continuously reboot and give a "watchdog error". Pull the module out and the router works fine (aside from the dead ethernet port).

This wasn't a big deal because the seller refunded half of my purchase price due to the dead module.

So, I get online and buy another NM-4A/S. It comes in the mail the other day and I pop it in the shady 2620. I connect it to a WIC-1T on another router and boot both up. I get the config on both ends and the link shows up/down. I troubleshoot for a while but never get it to come up. I reboot the router......and get a "watchdog error" with continuous reboot. I tried the module in 2 other routers and never got any to boot. They all went into the same loop with the "watchdog error".

I saw that module boot ONE time in the suspect router and now it causes a loop in any box I insert it. Is this a common occurrence with bad routers? Have you ever seen one kill multiple cards? I've sent the latest NM-4A/S back under warranty, but when I get the replacement I gaurantee it won't go in that 2620.

wbosher

Not sure if this is the same thing or not, but have aread of this - https://www.cisco.com/application/pdf/paws/7956/crashes_watchdog_timeout.pdf

chmorin

It is probably more likely that you are getting crap NM's from ebay than anything else.

tiersten

What chmorin said. It is more likely that you're getting broken NMs or the NM connectors are bad than that router is killing your NMs.

Your sample set is too small to give any conclusive indications about what is causing the issues.

Check that the connector on the NM and inside the router is clean and not tarnished.
Make sure that it is fully inserted. You get bizarre errors and problems if it isn't fully in because the partially inserted NM plays havoc with the CPU bus.

xenodamus

You may be right. I guess I'll find out when I get my replacement in....