Once you have the FUS file and the AireOS file downloaded to your local machine (or an accessible TFTP/FTP server), the upgrade procedure is as follows:
: Navigate to Commands > Reboot to apply the new firmware. The WLC will boot with the new "Primary" image while keeping the old one as a "Backup". Troubleshooting & CLI Solved: WLC 2504 firmware upgrade - Cisco Community cisco wlc 2504 firmware download work
This method has proven successful for many administrators without active contracts, particularly when security vulnerabilities or critical bugs necessitate an upgrade. Once you have the FUS file and the