MBP 2011 won't boot into Snow Leopard external HDD

hi, guys -

i've got a late 2011 MBP running Lion 10.7.3. i recently formatted an external Seagate HDD to run Snow Leopard and i thought that i could just boot into the external HDD by holding down the Option key on restart.

apparently, you can't.

does Lion just refuse to recognize the SL partition on the external? or does something on the new hardware say 'No' to an older OS?

i've tested booting the Snow Leopard external on another older MBP (Santa Rosa) running the same version software and that worked fine.

is there now hope booting to the Snow Leopard external from Lion?

if this has been posted elsewhere before, apologies and please feel free to send me the link.

thanks in advance.

InuNacho said:

Are you doing this over Firewire, I believe thats the only way how.

When I wiped Lion of my refurb 2011 I installed 10.6.3 from a retail SL disk on an external Firewire drive from a 2008 Macbook, booted onto the drive on the Macbook and updated it to 10.6.8. From there all I did was plugged the drive into the MBP, held down the option button and booted from the drive.

It's pretty slow over FW.

Click to expand...

you know what, the Seagate HDD is off of USB. think that's the issue?

i was hoping to test this on a Mini i was intending on getting and booting from the external SL HDD from the Mini, but if i'm having this issue testing on Lion, it may not be feasible.

anyone have any success stories?