adding a switch to a existing switch stack 3750?

[baselzind]

i need to add a " WS-C3750X-48PF-L" to a existing two "WS-C3750X-24P-L" , my question is if i set the ios into the same as the remaining two when i connect the stack cables , will it automatically get the configuration of the rest of the two?

-i plan on setting "switch#priority 15" on one of the existing switches so it will become the master switch  

[Leo Laohoo · Accepted solution]

Yes it will.
WARNING: Make sure the new switch is POWERED OFF before connecting the stacking cables. Failure to do so will cause the entire stack to reboot.

[Joseph W. Doherty]

". . . will it automatically get the configuration of the rest of the two?"

Yes and no. It will appear as another member switch, with unconfigured ports unless you preconfigured them. Once you save the running config, it will get a copy of it.

"i plan on setting "switch#priority 15" on one of the existing switches so it will become the master switch"

BTW - One of your existing stacked switches is already the master. Setting priority won't have an effect until there's another stack election.