Upgrading IOS on 3750 stack

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Mar 9th, 2009
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I have to upgrade our IOS on a 3750 stack. Do I upgrade the IOS on the master stack, reload the stack, and then the others will copy the IOS automatically from the master?



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s.marino Mon, 03/09/2009 - 07:53
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I stack should be on the same IOS at this time. When you apply the upgrade to the stack master it will be copied to all the switches in the stack. Reload the stack and all the switches will be on the new IOS.

The link below will give you a detailed step by step process.


Sal Marino

hobbe Wed, 03/11/2009 - 01:34
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In theory that is how it should work.

However since murphy exists I do the following when upgrading.

copy the IOS bin file (I do not use the http interface) to each and every one of the flashes in the stack.



flash3:/ and so on.

Set the boot to the proper ios for all the switches in the stack.

If this is the first time you upgrade the switches I would recomend my way to do it since IF there is a faulty flash you will get an error and have time to get another one to replace it before reloading the switches. (we found 2 in our environment)

as an added bonus you will get shorter stop time. ie the copying of the files to the flash is already done and the system will reload and come up in around 3.5-4 minutes depending if there are any upgrades in the microcode.


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