Stack Headaches
Last night I was had a simple task of adding a new 3750 to an existing stack. I went in thinking it would be a cake walk as they auto-upgrade and basically I was just going to have to rack it and connect some stack cables. Like most things recently there was more to it. This customer happen to have a very old 1.5U 3750 with 16mb of flash. It happened to be the master of the stack as well. This proved to be very annoying when trying to get the switch in the stack. The first problem was the current revision of code was too old and since the new switch was a later hardware revision it refused to auto-upgrade since it wasn’t sure it could support it. The customer used the web interface so I did the archive upgrade reloaded the stack and when it came back up only the first two switches actually upgraded. The new switch was still on the old revision. I then attempted to manually start the upgrade only to run into “Unable to create temp dir “flash:update”" error. This was quickly resolved with a “delete /recursive /force flash:update”. Unfortunately this is when I discovered that since it only had 16mb of flash it didn’t actually have enough to store the image for auto upgrades. After about an hour and a half I said screw it, loaded the bins on them and reloaded the stack… Victory was mine!
Morals of this story:
- Look at which switch is your master. If it is an old hardware revision be prepared for some issues
- Check the amount of available flash on your master switch. If it is only 16mb auto-upgrade most likely will not work.
- When push comes to shove you can also just load the .bin files on all members manually (TIP: Use copy flash1: flash2: etc… to save time when loading it between stack members)