ios is for 2811 or 2821

Unanswered Question
Feb 28th, 2012
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I have 2811 and 2821 routers in my branches

And decided to upgrade to 12.4(20)T

I find the ios for both download has the same name


also have the same size also have the same MD5

So how to differentiate between both files if I don't know what is for 2811 and what is for 2821

I have tried to upgrade a 2821 router with the 2811 ios file, the router didn't warn me, I think he should at least say no compatible bin file

Or what I think now is that each ios file can upgrade both routers !!!

any advise is appreciated


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Leo Laohoo Tue, 02/28/2012 - 20:44
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2811 and 2821 share the same filename.

2801 IOS filename starts with a 2801.

Joseph W. Doherty Wed, 02/29/2012 - 06:28
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If I remember correctly, the 2851 can use the same IOS image too.

Realize, often within a family seires, the major differences are device size and/or speed of the processor.  In such cases, the IOS image can be the same.


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