IOS XE Firmware Upgrade

[eyesishissin]

I've inherited some ISR4431 and ISR4331 routers with ROMMON 16.12(2r). I checked the release notes and saw this was recommended prior to upgrading to 17.6.x.

16.12.x => 17.6.5a

I want to upgrade to this version first before going to 17.9.x train (since 17.6.x will soon be EoL for security patches).

However, I noticed there was also a recommended CPLD version (never heard of this....). I did some digging, and found that this isn't a requirement, unless the router tells you after the IOS upgrade and Cisco recommends doing this after an IOS XE upgrade. From your experience, how true is that?

[Kasun Bandara]

@eyesishissin hi, recently i upgraded few routers to 17.9.4a as a security compliance. my routers already upgraded to 16.12(2r) rommon and did direct upgrade to 17.9.4a. did not had separate upgrade for CPLD. if you want you can do ROMMON and IOS upgrade in same process too.

https://community.cisco.com/t5/networking-knowledge-base/cisco-isr-amp-asr-1k-routers-ios-xe-firmware-upgrade-install/ta-p/4426457

[Leo Laohoo]

Cisco ISR & ASR 1k Routers: IOS-XE/Firmware Upgrade (Install Mode)