As much as I enjoy my 3750 switches and their stackability, I haven’t had much love from the 15T of IOS images. High CPU, counters that show high drop rates (Bug CSCtq86186), etc….
So, I have been downgrading some code. So much fun since it could change the microcode at the same time and take what seems like forever to reboot.
Anyway, it is quick and easy to downgrade/upgrade these guys, the quick and easy…
Log into the switch after you have the image you want and issue the following command:
switch# archive download-sw /overwrite tftp://ip_address/c3750e-universalk9-mz.xxx-xx
The /overwrite switch is a little scary since it does delete the existing image before installing to flash, but some switches just don’t have the size needed to keep more than one image.
Watch it load…isn’t this the fun part? Wait until you see the following:
All software images installed.
I still like to make sure since I am always paranoid. I check flash: and the boot commands to make sure the correct image is ready to go:
switch#: show flash:
Directory of flash:
/ 2 -rwx 1996 Mar 30 2011 01:48:06 +00:00 vlan.dat
536 drwx 512 Mar 30 2011 02:08:27 +00:00 c3750e-universalk9-mz.xxx-xx
switch# show boot
BOOT path-list : flash:/c3750e-universalk9-mz.xxx-xx.xxx/c3750e-universalk9-mz.xxx-xx.xxx.bin
Once satisfied, do the reload and wait….wait….wait. 🙂
I have had a stack ‘forget’ my credentials, so I went through a password recovery (oh, the fun there). Let’s hope you don’t go through that loveliness…especially around midnight since you are doing this during a scheduled maintenance window…right?
If you happen to run into this gem after extracting the files into flash:
The image in the archive which would be used to upgrade system number 1 does not support the same feature set.
Add the /allow-feature-upgrade to your archive command:
archive download-sw /overwrite /allow-feature-upgrade tftp://blah.blah.blah
Check this helpful post out regarding that error: