Please read documentation before upgrading your system.
We decided to upgrade from software version 6.2.4 to 6.2.5. It is going to be done with console access.
It is easy to upgrade, but you must know what to do with command download.
Firstly, you need a new software, an USB 2.0 flash with software on it or a TFTP server (tftp32, atftpd, ...). Then you have to realize that you have a correct version already running on your stacks:
# show boot
# show system verbose
So we have diagnostic image 126.96.36.199 which is already newest in time of writing this (2013-02-05). Switch runs firmware from primary 6.2.4. Firmware version 6.1.7 is set as secondary (there is a lot of difference between 6.1.7 and 6.2.4). Note - switch always boots primary. But you direct it to boot secondary with command "boot secondary".
Our situation is simplified, because we have two pure (not mixed with 5500) stacks forming a cluster.
We are going to "upgrade" secondary boot image first.
# download address 10.255.253.3 primary image 5xxx_625027s.img no-res
Then. You can check status of upgrade observing switch port LEDs. Duration download and saving firmware to two-switch stack is between 4 and 5 minutes. Please read documentation for more information. After that you can see with # show boot, that there is no secondary image on primary Switch #1. This should be fine.
After booting new image
# reload force minutes-to-wait 1new image will boot. But you have a problem. Secondary is still 6.1.7 and you want 6.2.4.
Here I noticed some kind of bug. Command:
# download address 10.255.253.3 secondary image 5xxx_624011s.img no-resdid not upgrade secondary image but primary. So I have again 6.2.4 as primary and 6.1.7 as secondary. (I tried this scenario multiple times with same starting situation even with restart after doing upgrade of secondary. )
After I put command
# download address 10.255.253.3 secondary image 5xxx_624011s.imgagain (2nd time) it fortunately upgraded secondary. So for now we have 6.2.4 and 6.2.4. Now you can upgrade primary with new software
# download address 10.255.253.3 primary image 5xxx_625027s.img no-resHere you should have 6.2.5 and 6.2.4 on primary and secondary installed.
I find some kind of helpful this command:
# boot secondary
Boot image = software = firmware
Sometimes a diagnostic image is named firmware.
Use this procedure to toggle the next boot image.
Use this procedure to use the secondary boot image.
Documentation: google for NN47200-500_06.02 or NN47200-500 Configuration System