If you see 16.x or 122-8r , you are several generations behind and should upgrade to 173-1r .
The 17.3(1r) release is a major milestone for the ASR 1000 series, often required for compatibility with modern Cisco IOS XE 17.x software branches A critical characteristic of this version is its irreversibility asr1000-rommon.173-1r.spa.pkg
After completing the ROMMON upgrade, follow this checklist to ensure everything is functioning correctly: If you see 16
The is a specialized firmware package used to update the ROM Monitor (ROMMON) on Cisco ASR 1000 Series Aggregation Services Routers . As a critical low-level bootstrap, ROMMON is responsible for initializing the router's hardware and loading the Cisco IOS XE software . If you see 16.x or 122-8r