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ios is for 2811 or 2821


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


Hall of Fame Super Gold

ios is for 2811 or 2821

2811 and 2821 share the same filename.

2801 IOS filename starts with a 2801.

Super Bronze

ios is for 2811 or 2821


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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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