I originally stacked 5 3750's using the stackwise cable. Everything worked nice because the first switch was stack1-1, the second was stack1-2, third was stack1-3 ... Now I have added 2 addtional switches (7 in total) and it appears to randomly assigned stack numbers to the switches and even changed the original switches.
Is there a way to specify which switch is which in the stack (so they are sequential top to bottom in my rack?)
Here is how you renumber the stack:
Go to global configuration mode.
Issue the command switch current-stack-member-number renumber new-stack-member-number .
Return to the privileged EXEC mode and reload the member with the command reload slot current-stack-member-number .
After the member boots up, issue the command show switch to verify the stack member number. If the number is used by another member in the stack, the switch selects the lowest available number in the stack.
Here is more relevant information on how to further manage your stack: http://www.cisco.com/en/US/products/hw/switches/ps5023/products_configuration_example09186a00807811ad.shtml#number
Hope this helps!