Upgrading IOS on router - not enough space

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Jun 17th, 2008
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I need to upgrade the IOS on an 878 but there's not enough space to hold both images on flash at the same time - what's the best way to go about this? I've read somewhere that you name the new image the same as the old and overwrite, but I'm not sure if this is right. Also the less risk involved the better!

Many thanks,


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Overall Rating: 4 (2 ratings)
Pravin Phadte Tue, 06/17/2008 - 06:41
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You can upgrade the new ios image without renaming the old ios.

If you are sure about the power to the router you can del the old ios and upgrade the new one. There will be no risk involved unless the ios goes bad.

I would strongly recommend not to rename the new ios with old ios. Also be sure of the dram to support the new ios.



jigsaw2026 Tue, 06/17/2008 - 07:32
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Thanks for your responses guys.

So basically I:

delete current image

download new image

change boot system to boot from new image


Is this correct?

Also, what happens if I delete the old image and then can't download the new? I guess I can use xmodem if necessary.

Collin Clark Tue, 06/17/2008 - 07:35
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That is the correct order. I would make sure you can access the TFTP/FTP/SCP/HTTP server before transferring the image. You can test by copying your config to TFTP server first.

Pravin Phadte Tue, 06/17/2008 - 07:59
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I would do in it some other format.

Download the ios.

check the min flash and dram.

del the ios

upload the new ios.

if there is only one ios you dont need to set the boot




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