Dual Boot questions

[obieJon]

Hi,

Relative newb here...

I currently have two iMacs, one mid-2011 running the current OS, one mid-2008 running 10.6.8. I have legacy music recording hardware that requires me to keep a computer on 10.6.8. However, the old iMac does not really have enough processing power to run all that smoothly.

I'm looking at the following computer on Craigslist:

Apple Mac Pro 5,1 MC561LL/A
2 x Intel Xeon E5620 (2.4GHz)
40GB DDR3 1066MHz RAM (Bought from OWC)
ATI Radeon 5770
Apple RAID Card (Needs new battery)
2 x 1TB WD Black HDD
Sonnet Tempo SSD Pro
2 x 120GB Intel SSD
2 x eSATA bracket installed

Will this be able to run one drive on 10.6.8 and one on the current OS? How would I go about doing that?
Thanks for your time and expertise!

 

[glawrie]

Yes, it should be able to do so without any problems. How you do this will depend on how often you plan to run either / both OS's - but one very simple approach would be to install the two OSs one on each of the SSDs. Then when you startup the mac, hold the "alt" (or "option" on some keyboards) key down until you see the first apple logo - then the mac will flip to a screen where you can choose which of the installed OS's you want to start up using (you can also do this for the next boot via a system preference setting "startup disk").

To make sure that the mechanical drives are visible to both OS's just make sure that they are formatted using HFS+.

HTH

 

[obieJon]

Awesome! One other thing that I just was hoping that could be confirmed... is a MC561LL/A able to run Snow Leopard? I gather that the Mac Pro is from 2010 and I believe Snow Leopard was 2008-ish. I definitely don't have the original installer... what is the best way to go about installing?

 

[DeltaMac]

Your 2010 MacPro originally shipped with Snow Leopard, so that will work very well
Apple still sells the Snow Leopard DVD, so that's a good option for you.

One problem, however.
The Snow Leopard version that your MacPro came with from Apple was a special build of OS X 10.6.4 -- newer than the installer on the DVD that Apple sells.
It's a challenge to install a fresh Snow Leopard install, but can be done.
Much simpler would be restoring the old iMac to the MacPro, which should leave you with a bootable Snow Leopard system on the MacPro. Search for "Reinstall OS X using Target Disk Mode"

 

[obieJon]

Thanks for the info! Wouldn't my old iMac need to have an installation DVD or image of 10.6.4 and up though? If not... how?

Your 2010 MacPro originally shipped with Snow Leopard, so that will work very well
Apple still sells the Snow Leopard DVD, so that's a good option for you.

One problem, however.
The Snow Leopard version that your MacPro came with from Apple was a special build of OS X 10.6.4 -- newer than the installer on the DVD that Apple sells.
It's a challenge to install a fresh Snow Leopard install, but can be done.
Much simpler would be restoring the old iMac to the MacPro, which should leave you with a bootable Snow Leopard system on the MacPro. Search for "Reinstall OS X using Target Disk Mode"

 

[DeltaMac]

Thanks for the info! Wouldn't my old iMac need to have an installation DVD or image of 10.6.4 and up though? If not... how?

You DID say that your old iMac has Snow Leopard.
All you need is a Firewire 800 cable to connect that old iMac to the newer MacPro.
Boot the MacPro to target disk mode.
Boot your old iMac normally. Launch Disk Utility, Restore tab. The old iMac is the source, and choose the drive of your choice on the MacPro to be the destination, and click Continue.
That transfers everything on your old iMac to the MacPro, including the system. All it takes is some time to let it finish.
When complete, you can shut it all down, then boot to the newly restored drive on your MacPro - and you have the Snow Leopard system, and everything else that you currently have on the old iMac. Should boot right up!

 

[obieJon]

Some successes and some failures to report! I successfully installed Snow Leopard on an HDD on the Mac Pro. The only issue is now I can't return to High Sierra because Snow Leopard does not recognize APFS drives and thats where the High Sierra boot is. So in retrospect I should I changed the drive format to MacOS before I started the process. Holding Option during restart results in a white screen forever or just a login screen for Snow Leopard. Same for command R. Any advice on how I can return to High Sierra in order to change the drive format?
Another strange but annoying thing: wifi on my old iMac (Snow Leopard) and the Snow Leopard boot on my Mac Pro is not working. I can't turn airport on or off and it isn't connecting to anything.
Thanks again for your time and help!

 

[DeltaMac]

Yes, you can't see an APFS volume from Snow Leopard (or while booted to any other OS X system up to Sierra).
However, it's simple enough to restart, holding the Option key.
Which Mac system do you normally prefer booting? If you are normally booted to High Sierra, you could leave the Startup Disk set for High Sierra. When you boot to Snow Leopard, just do that Option-boot, and choose the Snow Leopard disk for that boot.
If you don't actually change the Startup Disk setting, then a simple restart should restart back to High Sierra...

You might be able to get the wifi to work by doing a complete shutdown (so the power is off) before restarting to the Snow Leopard system. That might help, because a full shutdown can sometimes do a more effective reset of all the hardware (such as the wifi card) than a simple restart.
It's worth a test, anyway...

 

[obieJon]

Yes but holding down option doesn't seem to be working... just a white screen without the apple logo or a regular snow leopard startup. Any other ways?

 

[DeltaMac]

Are you using a third party (non-Apple) keyboard? Do you have another USB keyboard that you can try?

You have a relatively complicated drive setup, with the various cards/hard drives/SSDs - there may be a delay before the hardware brings up that option boot list.
How long did you wait? I would probably give up after after 3 to 5 minutes, then try an NVRAM reset, and try the Option-boot screen again immediately after the reset.

 

[obieJon]

Hi DeltaMac,

Just wanted to share with you the issue / solution. So I had the SSD mounted via PCI-e which apparently does not allow for option booting. I installed into a regular SATA slot with adapter and option worked... thanks for all your help!