Brand new 2012 quadcore i7 Mini. Can you boot from a USB hard drive?

[lokiju]

I've tried booting using two different USB 3.0 spec interfaces and a USB 2.0 interface.

I don't see why it would matter but might as well also mention it's a Samsung 830 SSD I've been trying with.

Am I doing something wrong or is it just not possible to run OS X from a external USB attached hard drive on the newest Mini's?

[Intell]

You're likely doing something wrong. Every Mac since those introduced in late 1998 have been able to boot via USB.

[sammich]

Originally Posted by Intell

You're likely doing something wrong. Every Mac since those introduced in late 1998 have been able to boot via USB.

Really? I remember being told that the switch to Intel made that possible. Before it was only Firewire you could boot from externally (apart from over the network)

[Intell]

Originally Posted by sammich

Really? I remember being told that the switch to Intel made that possible. Before it was only Firewire you could boot from externally (apart from over the network)

Yes, every Mac with a USB 1.1 or newer port can boot a USB drive. Only the USB 1.0 cannot.

[COrocket]

Originally Posted by lokiju

I've tried booting using two different USB 3.0 spec interfaces and a USB 2.0 interface.

I don't see why it would matter but might as well also mention it's a Samsung 830 SSD I've been trying with.

Am I doing something wrong or is it just not possible to run OS X from a external USB attached hard drive on the newest Mini's?

Did you properly format the drive and then make a copy of the internal hard drive? Or use internet recovery to install a fresh OS? A few more details would help diagnose the problem.

[jmcgeejr]

Originally Posted by COrocket

Did you properly format the drive and then make a copy of the internal hard drive? Or use internet recovery to install a fresh OS? A few more details would help diagnose the problem.

I have found that ccc and superduper dont work for me with cloning from internal to external. My suggestion is to just do an internet recovery and install from new on the new drive and then restore from the old drive all data and such.

[Mojo1]

It might be an issue with USB 3.0 and the Mac Mini. I'm dealing with OWC enclosures that will not spin-down when the Mini is powered-off.

I'm still working on the issue with Other World Computing...

[lokiju]

Originally Posted by COrocket

Did you properly format the drive and then make a copy of the internal hard drive? Or use internet recovery to install a fresh OS? A few more details would help diagnose the problem.

Internet recovery and selected the USB attached SSD.

[ybz90]

You cannot boot from a drive that is not GUID partition table formatted. Check with Disk Utility to see if you have them as MBR.

[Intell]

Originally Posted by ybz90

You cannot boot from a drive that is not GUID partition table formatted. Check with Disk Utility to see if you have them as MBR.

Intell iMacs can boot from a MBR drive and some of the eariler Intell ones can boot from an APM drive. Both via external and internal.

[lokiju]

Originally Posted by ybz90

You cannot boot from a drive that is not GUID partition table formatted. Check with Disk Utility to see if you have them as MBR.

Are you saying GUID partition is required specifically for USB/external drives? The current partition type is likely Mac OS Extended (Journaled) if so.

It was prior the only internal drive in my 2011 iMac. I took it out of my iMac when I sold it and without changing anything on the drive, attached it via the USB 2.0 adapter that Samsung packaged with the SSD, powered up the Mini while holding the alt/option key and it did not list the SSD as a bootable disk.

I then picked up a SATA III to USB 3.0 adapter made by Roswell (SP?) and tried the same thing and again, the drive wasn't listed as a bootable option.

That's when I tried doing Internet recovery and in the OS install it does see the SSD and let me pick it as a drive to install to but when it does the reboot after the install it sites for a good 5 minutes trying to boot then I assume fails and moves onto the next bootable drive which is the OEM internal 1TB drive.

In ML on my OEM internal when I go to settings and start up disk it list the SSD and I can select it and reboot but again it'll sit with a grey screen and spinning wheel for about 5 minutes then (I assume) times out and goes to the OEM internal drive.

I borrowed a friends USB 3.0 dock yesterday and tried that and this one did show the SSD as an option when booting and holding alt/option but wouldn't boot from it so I again did the internet recovery and it installed, reboot and in this case sat forever at the grey screen with the spinning wheel and never went past that. I had to force power it off, disconnect the USB attached drive and power back up to get past the grey screen with spinning wheel and back into ML on the OEM drive.

I wouldn't of thought it would be so difficult to accomplish this. I did some test using Blackmagic and the internal OEM drive was doing 58MB/s Write and 66MB/s Read. I then attached the SSD via USB 2.0 and tested with Blackmagic and was getting 38MB/s Write and 39MB/s read. Lastly I tried the SSD attached via USB 3.0 and was getting 181MB/s Write and 200MB/s Read.

I realize something like thunderbolt would be over double the USB 3.0 speeds from what I've seen other on here post but I would be ok with what the USB 3.0 speeds can accomplish since it's still a good bit faster than the internal and wouldn't require me ripping apart my brand new Mini and running the risk of damaging it.

[Bear]

Originally Posted by lokiju

Are you saying GUID partition is required specifically for USB/external drives? The current partition type is likely Mac OS Extended (Journaled) if so.
...

GUID is a partition table type. There are 3 types or partition tables that Macs can use for drives:

• APM - Useable as a data drive on Intel Macs, needed for PowerPC when used as a boot drive
• MBR - Use by windows and will be the default type for most external drives shipped preformatted with a windows filesystem.
• GPT/GUID - Needed for booting Intel OS X, useable as a data disk on PowerPC Macs.

Depending on which utility you use to look at the partition table type, it might use a slightly different name.

DIn DIsk Utility select the physical hard drive and look at the bottom of the window for "Partition Map Scheme:". On my system, it shows the boot drive as GUID. If I select the boot partition, on the bottom under "Format:" it shows "Mac OS Extended (Journaled, Encrypted)". For a drive you are doing a clean install on, you want it to be "Mac OS Extended (Journaled)".

[dasx]

The only bootable OSX in the last Mini is the one that comes pre-installed or the one you install by doing an internet recovery.

The version available in the App Store isn't compatible. If you download the 4.5GB Mountian Lion installation package and create a bootable USB it won't install on your 2012 Mini.

So, what are you trying to boot? If you did an internet installation on the external… then something's wrong, as you definitely should be able to boot from it.

[lokiju]

Originally Posted by Bear

GUID is a partition table type. There are 3 types or partition tables that Macs can use for drives:

• APM - Useable as a data drive on Intel Macs, needed for PowerPC when used as a boot drive
• MBR - Use by windows and will be the default type for most external drives shipped preformatted with a windows filesystem.
• GPT/GUID - Needed for booting Intel OS X, useable as a data disk on PowerPC Macs.

Depending on which utility you use to look at the partition table type, it might use a slightly different name.

DIn DIsk Utility select the physical hard drive and look at the bottom of the window for "Partition Map Scheme:". On my system, it shows the boot drive as GUID. If I select the boot partition, on the bottom under "Format:" it shows "Mac OS Extended (Journaled, Encrypted)". For a drive you are doing a clean install on, you want it to be "Mac OS Extended (Journaled)".

I'll double check it when I get home after work. Thanks for the thorough reply!

----------

Originally Posted by dasx

The only bootable OSX in the last Mini is the one that comes pre-installed or the one you install by doing an internet recovery.

The version available in the App Store isn't compatible. If you download the 4.5GB Mountian Lion installation package and create a bootable USB it won't install on your 2012 Mini.

So, what are you trying to boot? If you did an internet installation on the external… then something's wrong, as you definitely should be able to boot from it.

I'm not trying to boot a USB installer but a USB attached SSD that I run the OS (ML) from.

[Fishrrman]

Lokiju, you're making things too complicated.

It's easy to boot a Mac from a USB drive -- USB2 or USB3.

Very simple instructions:
1. Have your external drive connected
2. Use CarbonCopyCloner or SuperDuper to "clone" your internal drive to the external drive. This creates a bootable clone (and backup).
3. When done, restart.
4. As soon as you hear the startup sound, hold down the option key and KEEP HOLDING IT DOWN.
5. In a few moments, the startup manager will appear.
6. Select the external drive using either the mouse pointer or the arrow keys, then hit "enter" or "return".

The Mac will now boot from the external drive.
NOTE: This will not change the setting in the Startup Disk preference pane. If you restart again, the Mac will again boot from the internal drive, as before.

[lokiju]

Originally Posted by Fishrrman

Lokiju, you're making things too complicated.

It's easy to boot a Mac from a USB drive -- USB2 or USB3.

Very simple instructions:
1. Have your external drive connected
2. Use CarbonCopyCloner or SuperDuper to "clone" your internal drive to the external drive. This creates a bootable clone (and backup).
3. When done, restart.
4. As soon as you hear the startup sound, hold down the option key and KEEP HOLDING IT DOWN.
5. In a few moments, the startup manager will appear.
6. Select the external drive using either the mouse pointer or the arrow keys, then hit "enter" or "return".

The Mac will now boot from the external drive.
NOTE: This will not change the setting in the Startup Disk preference pane. If you restart again, the Mac will again boot from the internal drive, as before.

I've seen others mention cloning the OEM drive to a SSD but from what I've been able to tell this is always a way to avoid rebuilding everything and not some solution to some technical limitation that happens when doing a fresh OS install doing Internet recovery. Am I mistaken?

[ybz90]

Bear posted a great explanation. That may or may not be your specific issue, as the Mini is also version-specific as another poster mentioned, but if your partition table is not the correct scheme, it cannot boot no matter what.

[lokiju]

I've done it all now and still cannot get this Mini to boot from this SSD. It's not an limitation of booting from USB, that I am sure of. I booted from a USB with the Windows 7 installer on it today to install Windows via Bootcamp and that worked without issue.

I cannot get the SSD drive to list as a bootable choice when holding alt/option on start up.

I was trying to avoid tearing open my brand new Mini and risk things not going well but looks like I'll just suck it up and do just that now.

Thanks everyone who replied!

[Fishrrman]

"I cannot get the SSD drive to list as a bootable choice when holding alt/option on start up."

Did you follow the instructions I posted to you in reply #15 above?

There is no secret to booting via USB. You just do it.

You -DO- need an external drive that has a -GOOD COPY- of the OS on it, however.

[lokiju]

Originally Posted by Fishrrman

"I cannot get the SSD drive to list as a bootable choice when holding alt/option on start up."

Did you follow the instructions I posted to you in reply #15 above?

There is no secret to booting via USB. You just do it.

You -DO- need an external drive that has a -GOOD COPY- of the OS on it, however.

Yep. Used SuperDuper and it would not list when hold alt/option on boot. Using the very same drive, once installed internally, without changing anything else, booted without issue from that cloned copy using SuperDuper.

It's something very specific to this SSD and USB is all I can chalk it up to.

I completely agree it SHOULD be very simple, which is the only reason I did make this post, it does not work with this specific combination of SSD and model Mini.

Just for fun, here's the speeds of the Mini and SSD using different interfaces.

http://imgur.com/a/hae3p

The drive swap wasn't all that bad really. Probably easier than it was on the 2011 iMac.

[Mojo1]

Have you tried contacting Dave at SuperDuper! and see what he has to say?

If you post on the SD! forum you will hear back from him in minutes most days. I think the longest it has taken him to respond is around an hour...