Blog

I was upgrading a Catalyst 3850 48 port switch from version 03.07.01E to version 16.12.07. I’ve done this upgrade quite a few times. Followed the Cisco upgrade procedures that you find online when you download your software file. I always have them open, or the command needed to start the upgrade process. Console access showed me that my switch after my reload ended up in ROMMON mode.

As an experienced Cisco network engineer, you have often saved yourself from being locked out of a router when you make a change with a “reload in x” command. This handy command reboots most Cisco devices (routers, switches, firewalls) in the x number of minutes that you had specified. Thus, if you made a change that killed your connection to it, then you just have to wait until the time expires...

Two years ago Cisco introduced the Catalyst 9000 series switches as the next generation of campus switches. Every Catalyst switch family had an equivalent 9K to replace it; the 3800s were replaced with the 9300, the 4500s were replaced with the 9500, and the long standing 6500 chassis switches were replaced with the 9400. Cisco was consolidating all Catalyst switches into the 9000 series, well...

IOS XE supported switches such as the 3850 and 3650 support two modes, Bundle mode and Install mode.   New switches, by default, are shipped with install mode.   If you never paid attention during an IOS XE upgrade on a switch you may have just copy the IOS XE image to flash and set the system boot variable to boot from the new IOS using the command below: