Upgrading ROMMON is extremely safe when done correctly, but it carries more risk than upgrading IOS-XE.
For most production networks, this file sits quietly on flash, loaded once during a major lifecycle upgrade—and if all goes well, you will never need to interact with the rommon > prompt it helps protect. asr1000-rommon.173-1r.spa.pkg
This is a detailed technical piece on the file , aimed at network engineers and Cisco ASR 1000 series administrators. Upgrading ROMMON is extremely safe when done correctly,