Cisco 4500-X downgrade/upgrade procedure

Here is the upgrade/downgrade procedure for the 4500-X. For the record.

First upload the IOS archive (.bin) on the 4500-X. This can be done through tftp, scp or USB. My favorite way now is USB (the flash drive must be formatted in FAT32).

copy usb0:/xxxxxx.bin bootflash:/xxxxxx.bin

Then change the boot variable and write the configuration

(config)#boot system flash bootflash:/xxxxxx.bin

Make sure the configuration register is set to 2102 (take startup config and boot variable into account)

(config)#config-register 0x2102
(config)#end
#write
#reload

Updated on 10/12/2016.