Upgrade

Upgrading IOS on a Catalyst 3560 is not complicated, but the details matter: which file format you download, how much space is left in flash, and whether the boot variable points to the right image. A mistake in any of these leaves you with a switch that boots into the boot loader instead of IOS. There are two ways to do it: Method A: archive download-sw with a .tar file. The switch extracts the image, the web device manager files and sets the boot variable itself. Method B: manual upgrade with a .bin file. You copy the image, verify it, set boot system and reload. Lab note: I am upgrading my own Catalyst 3560 8-port PoE switch with both methods. Console outputs and timings from that lab will be added to this guide. ...

This guide covers the Cisco Nexus NX-OS software upgrade process in a practical, step-by-step manner — including rollback and recovery scenarios. The goal is to minimize service disruption and ensure the device can always be recovered in case of failure. Most upgrade failures are not caused by the upgrade itself — they are caused by skipping preparation steps. This guide treats preparation as seriously as execution. Cisco Nexus NX-OS Upgrade Process For out-of-band access during upgrade failures, see: The Backdoor of the Network: Next-Gen Console Server Architecture ...