Stacking Cisco 3750 Switches

I have two new Cisco 3750 switches that I'd like to stack, but they are currently running different IOS versions. One is running 12.2.44 and the other is 12.2.20. With this being said, I'd like to upgrade them to the latest IOS version. Should I do this to each switch before I stack them or can I stack them first and then do it?

Also, since these have never been configured or anything, can I just stack them from the get go or do I need do something first?

Thanks for the help. My Cisco knowledge is above beginner and that is about it.
hh_techservicesIT DirectorAsked:
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pitchfordConnect With a Mentor Commented:
I would flash them to all the same version; though it wouldn't surprise me if it didn't matter. The versions are too far off from one another; but better safe than sorry. I also assume you're doing a real stack and using the stack cable (whatever they call it) and not using port channels...

Refer to:
mikegattiConnect With a Mentor Commented:
I would upgrade the two switches to the same IOS version before stacking, you can definitely upgrade after without a problem. After that its just connecting the stack cables in the back and you are set. You can configure the switch that you want to be the master switch of the stack with the command:

switch stack-member-number priority new-priority-number

Here is a good link with info that can help you:
hh_techservicesIT DirectorAuthor Commented:
Thanks for the help, I'll look into those links. One more question for you guys. Is there any way to upgrade the switches to the newest IOS without configuring the switches first. I was hoping I could just connect to the console port and upload the newest version. But I believe I have to assign a dummy IP and then put the TFTP server on my laptop and connect it to the switch. Is that correct?

Sorry. I'm use to ASA's and using the ASDM to load the IOS really easily and then using CLI.
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SeeMeShakinMyHeadConnect With a Mentor Commented:
yes, unless you want to upload over xmodem (very painfully slow), you will assign interface vlan 1 an IP address and subnet mask and connect a TFTP server (or just laptop running a tftp daemon) to upload the IOS.

copy tftp flash

follow the prompts and enter the IP of the TFTP server and the IOS name and it will copy over.  sometimes, you have to delete the flash that's on your switch beforehand because there isn't enough room.  If you are using the webgui version of flash (the ios will have a .tar extension), then use the following command:

archive tar /xtract tftp://<ip address of tftp>/<ios_name.tar> flash:
BTW, if you need to delete the old image, you use linux commands for this.  Examples:

dir (shows directory contents)
cd (change directory)
rmdir (removes a directory - contents must be empty)
mkdir (makes a new directory)
del (deletes a file)
some tftp servers have problems with images over 32megabytes in size, not sure about the size of your image.
3750 IOS shouldn't be over 32MB
FideliusConnect With a Mentor Commented:
If you have tar version of IOS, you can upgrade through webgui. Just setup IP address as SeeMeShakinMyHead suggested in one of his posts. Point your browser to switch IP. Depending on current software it should look something like this:

If you need good TFTP, you can use 3Cdaemon:

Bm p
hh_techservicesIT DirectorAuthor Commented:
Sorry for the delay in getting back with this. Was out of commission for a couple of day. Thanks again for all help and different ways of doing it.
hh_techservicesIT DirectorAuthor Commented:
Thanks for all the help with this. I have both switches running the latest IOS. I did have to use xmodem because I was having troubles with TFTP and Windows 7 Firewall. Long story, but after using xmodem at 9600 (so slow) and then 11520 I feel like I'm an xmodem expert now.
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