Users may experience an issue when upgrading the firmware on Cisco SG300-10P 10-Port Gigabit PoE Managed Switch with the error message of “Illegal software format”

The upgrade has to be carried out using the CLI along with a TFTP server. This issue I experienced was upgrading from 1.3.0.62 to 1.4.0.88

To upgrade to 1.4.0.88 from 1.3.0.62 you have to install the version previous to 1.4.0.88 first. Let’s see how we do this:

See what version we are currently running
SW1#sh ver

Upgrade firmware
SW1#copy tftp://tftp_IP_address/path_to_the_file/1.3.7.18.ros image

Upgrade boot
SW1#copy tftp://tftp_IP_address/path_to_the_file/1.3.7.18.rfb image

Check boot images which are installed and make active
SW1#sh bootv

Image Filename Version Date Status
----- --------- --------- --------------------- -----------
1 image-1 1.3.0.62 02-May-2013 14:55:01 Active*
2 image-2 1.3.7.18 10-Oct-2013 17:15:41 Not active

SW1#boot system image-2
SW1#reload

Once the switch has rebooted do the same but with the files for 1.4.0.88