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I have three Cisco 2960G switches that I pulled from a working environment. All three of them are experiencing the same problem, so I have a hard time believing they have all simply failed.

Here's the problem:

When I plug in the power, all the ports lights flash once and the SYST, RPS, STAT, DUPLX and SPEED lights come on for a second. Then all the lights turn off, except for the SYST light which stays green. Nothing ever appears on the serial console. Holding the Mode button while applying power does nothing.

Do I really have 3 switches that all died at the same time?

longneck
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4 Answers4

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Open a TAC case as these may be affected by this Field Notice.

This revolves around a known memory issue by parts from a particular supplier that have a high failure rate. These parts have been included in many different platforms including many models of the 2960 line. You can find the main page discussing this issue and providing a number of field notices here.

In particular, the failure can occur during normal operation, but won't interrupt service. It is only after the devices have been power cycled that they fail to boot.

Specifically to your issue, would be this excerpt:

The failure symptom is observed when the switch fails to boot up with no console response (no characters are written to the console).

YLearn
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6

This is not a fix but a workaround to get your switch boot up. It did worked on my 2960G.

WS-2960G has a reset switch SW2 that hasn't been soldered (see picture). By shorting those two soldering points couple times I managed to boot the switch correctly.

It appears that the affected memory will not initialize immediately after the switch is powered, but it will more likely initialize once the power is there and the hard reset applied.

WS-2960G-48 boot

Mike Pennington
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Tomeq
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You can fix the DRAM issue heating up the DRAM module using a simple heating gun. Just fixed 1 switch using this method. The issue involves the welding points of the DRAM modules, so you don't need to replace them.

Mauro Bollini
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The reset SW2 didn't work for me however the heatgun trick worked. What I did was open the cover of the switch c3750 plug in the console cable, and power, started putty. Then I heated up the memory for a few seconds with the switch still on I did a hard reset by jumping SW2 and that worked for me. Now I can access the switch.

Thank you very much

Mac Jay
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