Switch

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. ...

You inherit a switch, the documentation is gone, and nobody knows the enable password. Or a lab switch comes back from storage and the console asks for a password you never set. On a Cisco Catalyst 3560 you can recover from both without losing the configuration, as long as you have physical access and a console cable. This guide covers the two situations you will meet in practice: Method 1: keep the configuration. The switch boots without loading its startup configuration, you reset the passwords, and you put the original configuration back. Method 2: password recovery is disabled. Someone configured no service password-recovery. You can still get the switch back, but only by resetting it to factory defaults. Lab note: I am running these procedures on my own Catalyst 3560 8-port PoE switch. Console outputs from that lab will be added to this guide. ...

Sooner or later every network engineer sees it: after a reload, the switch does not come back. On the console there is only a switch: prompt. The IOS image is missing, corrupted, or the boot variable points to a file that does not exist. This is not a reason to replace the switch. The Catalyst 3560 boot loader has everything you need to get IOS running again, even when the image in flash is gone. This guide covers: ...