Setting up OS X to simplify future clean installs

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Level 4

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Setting up OS X to simplify future clean installs

I prefer to carry out clean installs of new OS X versions (and I know the views vary on whether this is necessary; this is just how I do it).

I have recently bought a Macbook and was wondering if my idea below would work for installing OS X to simplify future clean installs. I should add that there is only one user account on the computer.

My idea is to partition the SSD into two volumes, one smaller and one larger. The smaller volume would hold Mavericks only. The larger volume would hold my user folder, all files and all software I install myself. The software I use is Photoshop CS6 and MS Office for Mac 2011.

Would this work? Are there any other things I should consider?

Many thanks in advance for your help

Philip

Posted on Jul 8, 2014 10:07 AM

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Answer 1

pullman Author

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Jul 8, 2014 12:48 PM in response to pullman

Anyone? I would really appreciate any insights before I decide to wipe the notebook.

TIA
/p

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Answer 2

Drew Reece

Level 6

10,660 points

Jul 8, 2014 3:47 PM in response to pullman

You can store the /Users folder on any disk provided it is mountable at login (clearly that should be the case with another partition on the boot disk). I think it's best to setup an admin in the default location and then set your own user account to be on the second partition via the 'Advanced user settings' (right click the User in Users & groups to set the home path).

It doesn't really simplify a 'clean install' because you cannot totally erase the HD, you can only erase the filesystem on the boot partition. If you plan on trying things that alter the disk (like installing Linux/ Windows, or using risky *nix tools like dd etc 🙂) your idea doesn't help, but it should be OK for someone who doesn't touch the partition table.

Also bear in mind that 'user level issues' may still exist if you install bad apps into your account, bad plists & weird cache issues will still occur.

You are also going to be juggling data based on what you guess are reasonable default sizes now - this could (and always does IMO) change in the future.

Think about how you can backup & restore this system too. I think having a few external disks in addition to bootable backups may be a more practical approach to moving data & restoring clean OS's.

It's up to you, personally I got tired of this approach years ago as some apps were insistent about saving data in their own locations - things like VirtualBox, Steam, Wine. It's tough to estimate how much these will bloat the user account or the boot partition. I do think it's reasonable to move the user home if you have a small SSD & a large spinning disk but that more out of necessity than choice.

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Answer 3

pullman Author

Level 4

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Jul 8, 2014 11:47 PM in response to Drew Reece

Thank you very much Drew, this is precisely the type of information I was looking for, personal experience and advice. Your help is much appreciated.

Yes, I was thinking of putting an administrator account on the OS volume to be sure I can access that. I forgot to mention this.

I'm not that advanced of a computer user but use it mainly for writing, image editing and a little bit of web development. So I don't touch the partition table or play around with risky tools. I did try out Bootcamp with Windows while on Leopard but decided it wasn't for me.

I accept that it is a difficult choice to know now how large the volumes need to be. I'll have to think about that a bit.

What you said about some applications preferring to save data in their own locations made me wonder if the more complex software I use -- Photoshop and MS Office -- really will install everything necessary on the "user/data" volume if I point their installers there. If not, then I will break those installations when I wipe the OS volume to carry out a clean install. I might post over at Adobe and Microsoft to see if I can find that out.

I have been thinking of an alternative to this and that would be to use Migration Assistant from a backup made just before the clean install/wipe. I am just not sure how well that works with Photoshop and MS Office. Any idea about that?

Cheers

Philip

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Answer 4

Drew Reece

Level 6

10,660 points

Jul 10, 2014 4:33 PM in response to pullman

Software installers will require an OS on the destination so you don't have any choice where Office & Photoshop are stored, they will need to go on the boot disk. The only thing I can think of from those apps that causes user data to grow is maybe MS Entourage's mail database, I can't think of anything that would cause issues beyond that.

Photoshop will use a scratch disk, but you could point it at either partition.

I forgot to mention things like swap & sleep images. These are hidden files the OS will store on the boot disk. Swap is used when RAM is all full, the sleep image is when the Mac is low on battery - it saves RAM onto disk so it can restart into the same state even if the battery dies completely. I'd try to leave enough space for these (the sleep image could be similar in size to your RAM. The swap file varies from about 1GB upwards).

I'd want to have 10-20GB free on the boot disk at all times.

pullman wrote:

I have been thinking of an alternative to this and that would be to use Migration Assistant from a backup made just before the clean install/wipe. I am just not sure how well that works with Photoshop and MS Office. Any idea about that?

I'm not sure I follow, whats your overall aim here?

You can backup either partition before any major changes & restore them if you need to do so later. Having user data separate is helpful for reinstalling the OS, but Migration Assistant won't allow you to copy data to any location beside the default /Users.

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Answer 5

babowa

Level 9

78,097 points

Jul 10, 2014 4:54 PM in response to pullman

Here is a different idea (and something I've done):

When I first got my MBP, I cloned the brand new system to an external drive using CarbonCopyCloner. I have since updated the OS and made incremental clones, but the original clone is still available on its partition just in case I need to start over (or want to sell the MBP as I need to sell it with the OS it came with per the SLA). That partition has not been updated and will not be - if I do need it, I can do it after cloning it back to the internal. It only has the default Apple applications on it since other apps come and go, get updated, etc, etc.

To me, that is about as clean as you can get.

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Answer 6

pullman Author

Level 4

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Jul 11, 2014 2:13 AM in response to Drew Reece

Thanks Drew for the further explanation and also Babowa for your suggestions.

From the Adobe forums I have learnt that it is not possible to put Photoshop in ~/Applications, rather it needs to be on the boot volume. I expect the same to be the case with MS Office. So this puts a spanner in the works for keeping the OS and only the OS on one volume and data and software on another.

I mentioned Migration Assistant because I thought it would let me migrate over software and data from a backup if I have wiped the drive and done a fresh install. But I guess it doesn't.

Anyway, thanks for your help.

philip

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Answer 7

Drew Reece

Level 6

10,660 points

Jul 11, 2014 5:50 AM in response to pullman

pullman wrote:

I mentioned Migration Assistant because I thought it would let me migrate over software and data from a backup if I have wiped the drive and done a fresh install. But I guess it doesn't.

Anyway, thanks for your help.

philip

You are right M.A. can move a backup copy back onto a Mac, but it is designed for the default setup where the user data is on the boot disk. Anything beyond that is going to require some work.

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