I would like to upgrade the IOS on a stack of 4 3750G's that I have. Is this upgrade only on the primary switch in the stack, or do I need to do all of them. They are connected via stacking cables.
Are there any gotcha's I should look out for?
I have done quite some upgrades and always used "archive download-sw /overwrite " command and have not had any issues. It takes care of setting the boot statement correctly, it removes older code from flash devices and makes sure that the code is in the flash of all the switches.
Since all three switches had the same IOS and the same bootloader, I did not concern over the reboot sequence, I just cycled the power on all three.
I used the same IOS on all three, my stack consisted of two 24 port gigabit switches and one 48 port PoE switch.
One of the 24 port switches is the master, but I did not take any special precaution to reboot.