Download the ISO file and the corresponding release notes for verified checksums. 3. Installation and Upgrade Procedure
When it was actively supported, ACS 5.5 introduced several major administrative and protocol enhancements:
: Using ACS 5.5 on a modern network is highly discouraged as it is susceptible to various security vulnerabilities and has not received updates for many years. Replacement
If you successfully recover an original ACS 5.5 base ISO, you must apply the latest available patches immediately.
. This is the modern platform for network access control, offering significantly better security and automation features. Do TAC still support ACS version 5.5 - Cisco Community
Document all Network Access Devices (NADs) along with their IP addresses and shared secrets.
Test authentication against the Cisco ISE server explicitly using test accounts before modifying production traffic paths. Step 4: Execute the Final Cutover