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

Vairamuthu

macrumors member
Original poster
Jan 9, 2013
47
1
Joburg
Hi all,

I have MBA 2011 13" 256GB.

I partitioned 150GB for system and 100GB for data and stored all data's.

If my OS get corrupted and i want to install a fresh copy of ML.

Do i have to format only system partition or do i have to format the whole hard disk?


Regards
Vairam
 

msjones

macrumors 6502
Oct 18, 2007
422
0
Nottinghamshire, UK
You will just be able to restore to the system partition without it touching your 'archive' partition.

However, if possible use time machine backups. Always better to have a backup of files and not need it.
 

Fishrrman

macrumors Penryn
Feb 20, 2009
25,311
10,330
"Do i have to format only system partition or do i have to format the whole hard disk?"

You would only have to re-initialize the "boot partition". No need to re-initialize and re-partition the entire drive.

As mentioned in reply #2, you should consider some kind of external backup.

I DO NOT recommend using Time Machine, however.

Instead, get an external drive with an overall capacity larger than the total of your internal (that is, 250gb or larger).

Then, partition it, just as you did your internal drive.

Next, download CarbonCopyCloner (or Superduper). You can get CCC here:
http://www.bombich.com/download.html

Now, use CCC to "clone" your internal boot partition (to your EXTERNAL boot partition) and then your internal data patition (to your EXTERNAL data partition).

Do this, and you will be fully protected against a failure of the internal drive.

A CCC backup is BOOTABLE and is also in POFF (plain ol' finder format) -- just mount it and "go". You CAN'T BOOT from a T.M. backup.

You can either buy an external drive, but I actually suggest you purchase the drive "core" and enclosure separately, and build it yourself. It's easy to do, and since you put it together, if anything ever goes wrong with it, you'll know how to take it apart.

I suggest this as an enclosure:
http://oyendigital.com/hard-drives/store/U32-M.html

Then find a 2.5" drive to go inside...
 

Vairamuthu

macrumors member
Original poster
Jan 9, 2013
47
1
Joburg
Thanks msjones and Fishrrman for your replies guys.

"A CCC backup is BOOTABLE and is also in POFF (plain ol' finder format) -- just mount it and "go". You CAN'T BOOT from a T.M. backup."

This sounds amazing . I already have a 1TB Ext drive.

Can i create partition exactly like my mac and do backup in that hard disk and use the remaining 750GB space for other purpose. Does the bootable option works in my 1TB.

or

The Backup drive should be a exclusive for MAC?

Thanks
Vairam
 

benwiggy

macrumors 68020
Jun 15, 2012
2,307
112
I partitioned 150GB for system and 100GB for data and stored all data's.
If my OS get corrupted and i want to install a fresh copy of ML.
Do i have to format only system partition or do i have to format the whole hard disk?
Several points worth raising here:
1. OS X rarely gets "corrupted". In ten years of using OS X (10.2 to 10.8), I've reinstalled the OS twice. Most problems are caused by third-party software or problems in the user account.

2. By default, a reinstall of OS X will replace the existing System files and leave your user data, apps and settings in place. So even if something goes wrong, there is no need to separate your files from the system (any more than the standard "user domain" is separate from the system).

3. You don't need to re-format either -- perhaps erase and install, but not re-format.

4. OS X expects to find stuff in particular places, and attempts to alter those locations can cause trouble.

5. I've never partitioned a drive and not wanted it to be different later. :D

Time Machine is excellent for data backing -- I see no reason not to recommend it. But CCC is ideal for making bootable clone images.
 

Weaselboy

Moderator
Staff member
Jan 23, 2005
32,965
13,205
California
Thanks msjones and Fishrrman for your replies guys.

"A CCC backup is BOOTABLE and is also in POFF (plain ol' finder format) -- just mount it and "go". You CAN'T BOOT from a T.M. backup."

This sounds amazing . I already have a 1TB Ext drive.

Can i create partition exactly like my mac and do backup in that hard disk and use the remaining 750GB space for other purpose. Does the bootable option works in my 1TB.

or

The Backup drive should be a exclusive for MAC?

Thanks
Vairam

Yes, you can make two or more partitions on the external drive and use one for backups and the other(s) for whatever you want.

There really is no need to partition the internal SSD though. The way OS X organizes user data it is very easy to just copy/backup that data if you want, and as other mentioned, an OS reinstall won't erase your data.

I would just leave one partition on the SSD and use the included Time Machine to backup the entire drive to your 1TB external. Maybe give yourself a 500GB partition on the external for the Time Machine backup. This will allow extra backup space for older versions of your data.

Also, a Time Machine backup can be used to boot and restore the entire system. All CCC adds is the ability to boot from the external and actually run from that disk if you have to.
 

Vairamuthu

macrumors member
Original poster
Jan 9, 2013
47
1
Joburg
I will try both Time machine and CCC .

I partitioned my 256GB in to 150 and 100GB. How can i make it as one single disk?

I felt my mac is getting slower when it was a single disk. Apps took long to start and had system freeze issue while startup.

After partition i am feeling its back to normal and no more freeze during the start up.

Thanks guys for your advice. Much appreciated.
 

benwiggy

macrumors 68020
Jun 15, 2012
2,307
112
I partitioned my 256GB in to 150 and 100GB. How can i make it as one single disk?

I felt my mac is getting slower when it was a single disk. Apps took long to start and had system freeze issue while startup.

After partition i am feeling its back to normal and no more freeze during the start up.
Use Disk Utility to create one partition.

Whatever your problem was, I suspect that partitioning the drive was coincidental, rather than the solution to the problem. It may have been as simple as rebooting that was the fix.
 

Vairamuthu

macrumors member
Original poster
Jan 9, 2013
47
1
Joburg
Got a new issues when using CCC.

I partitioned my External HDD 1TB to 160GB(for my system) and balance 840GB with all my data. I repartitioned the 160GB as Mac HFS. 840GB is partitioned on windows NTFS.

CCC can clone the mac to 160GB partition but can't clone Recovery partition .So i can't use this disk as startup disk.

complaining - The underlying disk is not partitioned with the GPT partitioning scheme.

How to partition my disk in way to accomodate the recovery partition with out causing trouble for my data in 840GB partition ?
 

Weaselboy

Moderator
Staff member
Jan 23, 2005
32,965
13,205
California
Got a new issues when using CCC.

I partitioned my External HDD 1TB to 160GB(for my system) and balance 840GB with all my data. I repartitioned the 160GB as Mac HFS. 840GB is partitioned on windows NTFS.

CCC can clone the mac to 160GB partition but can't clone Recovery partition .So i can't use this disk as startup disk.

complaining - The underlying disk is not partitioned with the GPT partitioning scheme.

How to partition my disk in way to accomodate the recovery partition with out causing trouble for my data in 840GB partition ?

You will need to use GPT with HFS+ to boot an Intel Mac and use the recovery partition. See the last post in this thread for a work around.
 

Vairamuthu

macrumors member
Original poster
Jan 9, 2013
47
1
Joburg
solved

I empty my 1TB Disk and did Guid partition in mac. 150 for Mac HD and Rest for the General Backup.

Cloned my System and created Recovery Partition .

Tested using Cloned disk as Startup , Everything works Fine,

Thanks A lot Guys..
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.