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L T

macrumors 6502
Original poster
Feb 24, 2013
433
108
UK
Hello people

In anticipation of the Yosemite Public Beta going live I would like a bit of help.

I only have 1 machine a, mid-2013 base 13inch Air, and would like to install the Yosemite beta on it although don't want to have my MacBook crippled by it!

I've see a couple of posts that suggest I can install Yosemite on a partition keeping Mavericks on the other bit. Guessing this would allow me to chose to boot Mavericks or Yosemite on start up?

Only problem is that I have only 11GB left of my 128GB storage, although I have 2 x 1TB external drives I could use.

So basically here are my questions

Can I install the Yosemite Beta onto an external HHD?
If yes, how??

How can I then boot from the external hard drive?

If I then boot to Mavericks as normal from my internal SSD everything will still be the same as it was yeah?


I like the idea of being able to try Yosemite from the external drive but always being able to boot back into Mavericks if I have any problems.


Thanks is advance guys
 

Liam555

macrumors regular
Jul 14, 2014
134
87
Using an external hard drive is the best thing to do. Just install yosemite onto the hard drive and then you can boot it up using the "startup disk" in your settings. Same thing goes to when you want to come back to mavericks from yosemite. Just click back on the internal "macintosh HD" from the startup disk settings and it will load you back to mavericks.

Also, nothing gets effects within your main internal HD. Once you stop using yosemite, you can then just delete it from your external HD.
 

L T

macrumors 6502
Original poster
Feb 24, 2013
433
108
UK
Using an external hard drive is the best thing to do. Just install yosemite onto the hard drive and then you can boot it up using the "startup disk" in your settings. Same thing goes to when you want to come back to mavericks from yosemite. Just click back on the internal "macintosh HD" from the startup disk settings and it will load you back to mavericks.

Also, nothing gets effects within your main internal HD. Once you stop using yosemite, you can then just delete it from your external HD.

Thanks

Guessing I have to download Yosemite and then move it to the external drive. When I boot to Yosemite it will be like setting up a new mac yeah?
 

JerTheGeek

macrumors 68000
May 15, 2014
1,993
487
Thanks

Guessing I have to download Yosemite and then move it to the external drive. When I boot to Yosemite it will be like setting up a new mac yeah?

What you do is download the Yosemite installer from the App Store using your redemption code that you'll receive via email. Then launch the installer and you'll get an option of where to install it. Just select the partition you created for Yosemite, and then reboot and hold down the option key. You'll see your partitions, select the one with Yosemite on it, and you'll boot into it and it will be like a new Mac.
Hope this helps.

EDIT-----OOPS, i thought you were trying to do it with a separate partition, not an external drive. Sorry! These steps will also work for an external drive though, just select the external drive when installing, and then select the external drive when rebooting.
 
Last edited:

UncleSchnitty

macrumors 6502a
Oct 26, 2007
851
14
Thanks

Guessing I have to download Yosemite and then move it to the external drive. When I boot to Yosemite it will be like setting up a new mac yeah?
NO they made it really really easy this time. Just run the installer and your internal drive will be there but right underneath it will say something like select other drive. Click that button, select your external and thats it. Very very easy.
 

springsup

macrumors 65816
Feb 14, 2013
1,263
1,303
The latest beta is pretty stable and, though you can't rule it out with beta software, you're unlikely to lose any data.

The thing you absolutely must do before installing, though, is to make a Time Machine backup. If you do this, you'll be able to restore your entire system to before you installed the beta.

Alternatively, you could install it in a virtual machine. If you do that, you can start off with a small virtual hard drive, then increase the size or even write it to a partition to boot natively later on.
 

Tiguan

macrumors member
Jan 26, 2014
64
79
What you do is download the Yosemite installer from the App Store using your redemption code that you'll receive via email. Then launch the installer and you'll get an option of where to install it. Just select the partition you created for Yosemite, and then reboot and hold down the option key. You'll see your partitions, select the one with Yosemite on it, and you'll boot into it and it will be like a new Mac.
Hope this helps.

EDIT-----OOPS, i thought you were trying to do it with a separate partition, not an external drive. Sorry! These steps will also work for an external drive though, just select the external drive when installing, and then select the external drive when rebooting.

Forgive me if I'm wrong but I just want clarification. I'm looking to install yosemite onto a partition of my current SSD (I've sat 75GB aside for that). I've never used a partition before and my question is this...

When (if) I decide that yes, yosemite is stable for me and I want it to be my 'main' startup disk, is it simply a case of heading into disk utility and deleting my Mavericks partition, thus freeing up that space for my yosemite partition? How does that work? I can't imagine you having to wipe it all and start again, but then what do I know, eh?! Thanks for your help :)
 

L T

macrumors 6502
Original poster
Feb 24, 2013
433
108
UK
What you do is download the Yosemite installer from the App Store using your redemption code that you'll receive via email. Then launch the installer and you'll get an option of where to install it. Just select the partition you created for Yosemite, and then reboot and hold down the option key. You'll see your partitions, select the one with Yosemite on it, and you'll boot into it and it will be like a new Mac.
Hope this helps.

EDIT-----OOPS, i thought you were trying to do it with a separate partition, not an external drive. Sorry! These steps will also work for an external drive though, just select the external drive when installing, and then select the external drive when rebooting.

Is it worth partitioning my external drive, it currently has amply iTunes library on ut
 

JerTheGeek

macrumors 68000
May 15, 2014
1,993
487
Partitioning a drive erases it doesn't it?

Not too sure about that; I partitioned the main drive on my MacBook Air, and everything is fine, nothing got erased. Again though, i don't know about your particular external drive.
 

Weaselboy

Moderator
Staff member
Jan 23, 2005
34,463
16,160
California
Forgive me if I'm wrong but I just want clarification. I'm looking to install yosemite onto a partition of my current SSD (I've sat 75GB aside for that). I've never used a partition before and my question is this...

When (if) I decide that yes, yosemite is stable for me and I want it to be my 'main' startup disk, is it simply a case of heading into disk utility and deleting my Mavericks partition, thus freeing up that space for my yosemite partition? How does that work? I can't imagine you having to wipe it all and start again, but then what do I know, eh?! Thanks for your help :)

No that won't work. You can resize partitions in OS X and also add and remove them, but there are limits depending on where the partition is. In your case Mavs is at the top in Disk Util, so you could boot to Yosemite and remove Mavs, but then you would not be able to expand it UP into the old space. You can only expand DOWN into free space BELOW the existing partition.

If you look at the lower graphic here you can see what I mean. See there how you can only move the bottom grabby thing at the end of the partition up or down. If that partition you were trying to resize (Yosemite in your case) was at the bottom there would be nowhere to expand it into.

So what you would want to do is say you decide later you are happy with Yosemite and want it as the only partition. You could command-r boot to recovery and erase the top Mavs partition then use the restore tab in Disk Util to clone the Yosemite partition over to the old Mavs partition (clone from bottom to top). Then option key boot into the new Yosemite clone at the top. Then is all is well, start Disk Util and remove the lower partition then expand the top one to fill all the space.
 

Tiguan

macrumors member
Jan 26, 2014
64
79
Thanks for your thorough explanation. It made perfect sense. As it turned out I simply bit the bullet and upgraded over my Mavericks OS. Touch wood, it has all turned out OK thus far and I haven't seen any major problems barr a couple of niggles here and there.

Thanks again :)
 
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