hi, I'm considering upgrading the flash memory in my 877, but I'm unsure what will happen when I swap out the 4gb flash for a 16gb flash.
The flash composes of on-board flash and the expansion flash module. My router has 20gb on-board and a 4gb expansion card.
What I'm not sure about is when I replace the 4 with a 16gb what will happen? Will the flash get corrupted? and sureley the IOS will be corrupted leaving me to XMODEM the IOS back?
I've done this before without a problem, but it's been a while. The most important thing is to first of all back up your IOS image and config to a local TFTP server as it will be gone after the upgrade. This will give you the chance to test your TFTP server for the next step :)
Whenever you pull the old flash and install the new one the router will complain but should boot into ROMMON. The quickest way to reload your IOS is via the ROMMON tftpdnld command - it's a lot quicker than xmodem. I think tftpdnld has to be done over FE0 and it is important to note that the commands are CaSe specific.
For more details see the 'Disaster Recovery' section of http://www.cisco.com/en/US/docs/routers/access/800/850/software/configuration/guide/rommon.html
Finally, there's a discussion of the issue at http://www.dslreports.com/forum/remark,16511692
The ninth post gives one person's guide to doing the upgrade. Good luck!