Sidebar Sidebar
Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

Restoring OS X

webpoet73

webpoet73

macrumors regular
Original poster
Jul 29, 2010
129
26
Alpharetta, GA
I have a question about post-installing OSX...

Is it better to
a) treat it as new and re-install apps and re-copy the data over from an existing backup
b) Use the user migration to pull users (and applications) from existing backup

Option b would definitely be easier. But would there be any advantage to option a?

I am seriously thinking about doing a full clean install of Mountain Lion on my iMac. It's three years old and been through Snow Leopard, Lion, and now Mountain Lion. I am thinking a clean install might boost performance a bit.
 
webpoet73 said:
I have a question about post-installing OSX...

Is it better to
a) treat it as new and re-install apps and re-copy the data over from an existing backup
b) Use the user migration to pull users (and applications) from existing backup

Option b would definitely be easier. But would there be any advantage to option a?

I am seriously thinking about doing a full clean install of Mountain Lion on my iMac. It's three years old and been through Snow Leopard, Lion, and now Mountain Lion. I am thinking a clean install might boost performance a bit.
Click to expand...

I think many people on this forum will disagree however when I had my 2007 iMac I never did a clean install, that was after migrating from Tiger to Leopard to Snow Leopard to Lion and finally Mt. Lion. In short 5 totally different OS's and I never had one problem. When I sold the machine to my friend I did a clean install of Snow Leopard because the Mt. Lion license isn't transferable.
 
If you have done a lot of install/remove apps in the past I would only transfer with Migration Assistant the user(s) and reinstall all the apps manually.You know that when you remove an app it always leaves some rubbish behinde and probably you don't want to move it forward to the next OS
 
If your system is working okay now, there really is no good reason to go through all the hassle of a clean install.
 
Once booted, it works fine. Every re-boot, after getting into the desktop, the hard drives very hard for 5 to 10 minutes. I get concerned. I have done all of the preventive measures in Disk Utility.

Unfortunately, even though I have a Seagate drive (ST31000528ASQ), my iMac did not qualify for the warranty replacement.

I don't have the skills to pull the iMac apart and replace myself. Just reading on the Apple Support forums, that might not be so easy. Something to do with the temperature sensor...

I may not do a clean install, then. Thanks, guys.

If I had to, could it be run off of an external firewire drive? In case of disaster...
 
If you're not backing up, then get a backup solution. Time Machine is pretty handy and will help with a fresh install and restore because it won't overwrite system files.
Also put the OSX install on a USB flash, much faster install.
 
Backup plan

Yes, I do have a backup plan.

a) I have ML install on USB stick
b) Time Machine on a local USB hard drive
c) I backup every couple of weeks (clone) to a hard drive that I take off premises in case of disaster.

I guess that a clean install is not needed, but it's been so long, it feels like it needs one.
 
You could just do the clean install and select the transfer user settings and files via a time mach backup.
 
Chris Blount said:
Don't worry. Install the OS and restore from your Time Machine. Things will speed up nicely.
Click to expand...

That is not a "clean install" and will put OP exactly where he is now. A TM restore will put every last setting and app back on the drive. If there are problems with the install, they will just be "restored" with this method.

A true clean install is a erase of the disk then install of the OS, followed by the manual installation of every app and setting.
 
BTW- Does anyone know if the AppStore version of Mountain Lion has been updated to 10.8.3?

I would like to update my 'rescue USB' to include my 2012 Mini and iMac.
 
MatthewAMEL said:
BTW- Does anyone know if the AppStore version of Mountain Lion has been updated to 10.8.3?

I would like to update my 'rescue USB' to include my 2012 Mini and iMac.
Click to expand...

Sure has.

screenshot20130320at121.png
 
It seems to be a idea from people who have used Windows regularly that in the event of any problem, the first thing you should do is to reinstall the OS.

On OS X, the OS is almost never the problem, and should not need reinstalling unless you've deleted or overwritten some system files. (Or given yourself write permissions to the whole disk, etc.)

You don't need to reinstall the OS because "it's getting slower", or as some kind of annual pagan ritual of cleanliness.

Most problems are likely to be fixed by emptying caches, deleting user preference files and removing third-party software. A clean install will of course empty the caches, so that's probably why you get an improvement. (Safe Boot will also do the same, so that's worth trying.)
 
Chris Blount said:
I never said it was a clean install. All I was saying is that when re-installing the OS then restoring the backup can clear issues with the OS itself. I've done this few times myself and it works. You won't know until you try it. It will NOT necessarily put the OP back where he was.
Click to expand...

Yes, it will. If you erase then reinstall the OS, and then use Migration Assistant to pull in data from a backup, that may help. But if you reinstall the OS then "restore" from Time Machine, it overwrites the OS install you just did with the OS and data from the Time Machine backup. It is a complete waste of time and accomplishes nothing at all.

I think you may mean import to a new install with Migration Assistant rather then the "restore" you keep mentioning.
 
Chris Blount said:
Pretty much true but as you said, the OS is ALMOST never the problem. Emptying caches, deleting user preference files is usually good start. If that doesn't work, re-installing the OS and restoring from Time Machine would be the next step. Doing a clean install is a last resort because it's basically a pain in the butt.
Click to expand...
Yes, my point exactly. Reinstalling is the LAST thing to try, not the first.
In ten years of using seven different versions of OS X across four computers, I've reinstalled the OS about three times. And probably not all of those were necessary.

Most system files are read-only, and not modified during their life. It's only the files in the "working" areas that are likely to cause you bother. Most of those in the user's Library folder, plus the top-level Library folder. You can easily sort out issues in those areas without doing a nuke and pave.
 
Chris Blount said:
Not true. Time machine does NOT backup the core OS. Time machine is designed to restore your settings, data and apps to a new OS installation. Go look it up.
Click to expand...

I'm sorry, but you are far far off here. Time Machine most definitely backs up the OS. There are countless threads here about users putting in a new, blank drive and doing a full system restore (including the OS) from a Time Machine backup. I just did it myself two weeks ago on a friend's Macbook Pro.

Read this.

screenshot20130321at943.png


You can also read more about it here.

Please read up a bit on this, because your posts are incorrect and it is confusing people.

A Time Machine backup does include the entire OS and it can be used to restore a system onto a completely blank disk without first installing the OS.

Again, if you install the OS, then "restore" from Time Machine, you just installed the OS for absolutely nothing because the TM restore wipes the drive and replaces whatever was there with the restore. Read this.

screenshot32113952am.png


I know it is very confusing, and frankly Apple has not done a very good job explaining how all this works, but you are quite wrong.
 
Chris Blount said:
Sorry, you are quite wrong. System files are NOT the core OS. Apparently you don't understand how UNIX works.
Click to expand...

Time Machine backs up the entire disk, including the OS. If you read the links I posted you would see this.

You want more proof. Okay... here, here, and here.

I don't see what is so difficult to grasp here. Just about every other day there is a post here about a forum member using TM to restore to a blank drive. So you think they are just making that up?
 
Hmmm... ok. I thought that a re-install would solve my iMac drive problem of constantly reading for like 5 minutes after a re-boot. Sometimes, it feels like it may never stop reading. I am kind of getting worried about the drive, itself. I can't repair an iMac, myself. I fear how much Apple will charge to do it.

I have had serious thoughts about the next Mac being a Mac Mini with a good 27" monitor. I won't be able to do that for a while (unless the iMac dies) because I just bought a Macbook Air, which could power a 27" monitor (but 128GB SSD is severely limited compared to 1TB drive...)
 
You must log in or register to reply here.
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.
Top Bottom
Back