This is typically done via the Command Line Interface (CLI) for stability during large file transfers.
Later firmware versions introduce improvements in RF (Radio Frequency) optimization, mDNS (Bonjour) gateway services, and better roaming algorithms. cisco 2500 series wireless controller firmware update
Upgrading the firmware on a Cisco 2500 Series WLC remains a straightforward but risk-sensitive operation. Adherence to a strict pre-upgrade checklist, careful transfer method selection, and a well-documented rollback plan are essential to minimize wireless disruption. Given the platform’s EoL status, organizations still operating 2500 controllers should prioritize hardware migration over further upgrades. Nonetheless, for those requiring one final security or stability update, the procedures outlined in this paper provide a reliable framework for success. This is typically done via the Command Line
config wlan enable <wlan_id>
Look for the "Predownload Status" to show "Complete" for all APs. config wlan enable <wlan_id> Look for the "Predownload