IOS-XE Denali represents Cisco’s effort to bring a single code base across their enterprise line of networking equipment, meaning the same operating system will run Catalyst, ISR, and ASR platforms.

IOS-XE 3.7 will be the “end of the track” for the 3.X train of code on Catalyst 3650/3850… so to speak.

Below are the steps I used to upgrade a 3850 from IOS-XE 03.06.03E to IOS-XE 16.3.5b Denali. The switches were in “install mode” and these steps are specific for that method. To check your mode you can issue a show version command and look under the Mode column. 3850s should come from the factory in install mode; bundle mode is similar to the older upgrade method where you boot from a monolithic bin file. More info on install mode and bundle mode can be found here.

Just got in a new Cisco ISR 4431 and needed to upgrade IOS-XE out of the box. Cisco has been nice enough to include a 1Gb USB flash drive with their new ISRs, making the software upgrade process a cinch. Here are the steps involved to install a new version of IOS-XE via USB drive.

• Download your chosen version of IOS-XE from cisco.com. Keep in mind there are often may different trains and revisions of code available.
  • To help you decide which version of code is right for you, there’s the cisco IOS feature navigator found here.
  • To help differentiate the different designations of code, i.e., MD, ED, GD, take a look here.
  • Typically I opt for a gold star release, which are cisco recommended releases “based on software quality, stability and longevity.”

the downloaded image to your USB drive and insert it into the ISR