Persistant switch SW update problem

[simonspivey]

I posted an earlier question, but things have got wierder.

I had a problem updating a BS-420 stack via telnet. Diagnostics upgrade failed, both switches do not boot past the 'Testing Main Memory - Passed' message.

Today, I put one on a bench, and tried the same with a console cable, TFTP server on switch port. Same problem.

This time I noticed a message:

Downloading BS420 Diag Image. Please Wait.
[/]Error code 0: timeout on receive
Programming BS420 Image. Please Wait.

This 'timeout' occurs almost immediately, and the switch resets in about 2 seconds. The TFTP server does not show the image file as successfully downloaded.

Why would it do this? Why would it attempt to program the flash if the image download failed?

How can I recover these 4 switches?

Thanks in Advance...
Si.

 

[telecom116]

Try this.

Hopefully, you have a Network Sniffer, or similar software available. Attach it to the 420 (or better yet, attach your sniffer to an old 10BaseT hub, then attach the hub to the 420.

Then, power up the 420 switch. I am going to surmise you will see a request from the 420 to TFTP download from a particular IP subnet or address.

What I'm thinking is that the switch's initial bootstrap is programmed to download code from some particular IP address; remember, the factory has to get the code on the first time somehow. Use your sniffer trace to see what its asking for may provide you a way of figuring out where it really wants the code at.