Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

upgrading flash

Can anyone tell me the normal procedure for a flash upgrade, do you need to remove the old ios first ?


Re: upgrading flash


Instead of removing the ios i can say you have to backup the old ios first.

So that you can proceed up without any hassels with upgrade process..


New Member

Re: upgrading flash

Hi there, So would I just do copy tftp flash and overight the existing file, is that the normal way !!

Re: upgrading flash


During uploading the new ios onto the flash you will be prompted for erasing the existing ios code if the flash space is not enough to load the new ios code..

Else if you have enough flash space you can keep the old ios code intact so that if you face any kinda booting issues you can very well recover/reload with the previous working ios code.


New Member

Re: upgrading flash

Hello Carl,

It depends on the type of flash (file system) you are working with really. There are three classes of flash memory - Class A, B, and C.

The Class A and C file systems use the erase and squeeze commands to permanently delete any existing files in the flash memory. Class B uses only delete, which only marks the files as deleted but they still occupy space in the file system. The only other option is erase, which erases the entire flash memory.

So, depending on your system, you need to determine what type of file system you are running.

Once you've determined you have enough space for the IOS image, you will need to tftp the new IOS from a server to your router/switch. Make sure you have a tftp server running that can be accessed from your router/switch. For a windows platform, tftpd32 works quite nicely.

Here is an example:

router#dir flash:

Directory of flash:/

1 -rw- 12848792 Jun 17 2005 08:19:04 -06:00 c2600-jk9s-mz.122-29.bin

16252924 bytes total (3393936 bytes free)

router#delete flash:c2600-jk9s-mz.122-29.bin

Delete filename [c2600-jk9s-mz.122-29.bin]?

Delete flash:file? [confirm]

router#squeeze flash:

Squeeze operation may take a while. Continue? [confirm]

squeeze in progress...

Squeeze of flash complete

router#copy tftp: flash:

Address or name of remote host []?

Source filename []? IOS

Destination filename [IOS]?

Accessing tftp://

Depending on your system, you may have to add the following command to your config:

router#boot system flash:c2600-jk9s-mz.122-29.bin

Anyway, I hope this helps.


CreatePlease login to create content