How to merge 2 partitions into 1 on El Capitan?

Barncore

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Original poster
Oct 7, 2014
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Here's my situation. I have a 1TB internal hard drive on my 12,2 iMac that, when i first got it, i split into 2 partitions. I got my refurbished imac shipped with El Capitan, but i wasn't ready to make the move from Snow Leopard yet since all my old music projects relied on the older software and plugins, so i made 1 partition 920GB to host my backed-up Snow Leopard system, and the other partition was 80gb so i could casually use El Capitan for a while and see if i liked it.

Fast forward almost 2 years and i finally upgraded my 920gb Snow Leopard drive to El Capitan (and all my software works fine), so now i have no i need for the 80gb El Capitan partition anymore, and i want the disk space. I just want 1 partition HD.

However there's software on the 80gb drive that i'd like to use on my final 1 drive too. So i'd like to either merge to the 2 partitions OR copy+paste data over to the 920gb and then deleting the 80gb partition.

Here's my setup...

The 80gb El Capitan drive is called "Macintosh HD". Or disk0s2:

80gb.png


^ I realize this drive is full. I can fix that if needed for functionality reasons?

The 920gb drive is called "SL 10.6.8". Or disk0s4. Despite the name, "SL 10.6.8" is running El Capitan as well (since today)...

920gb.png


^ This is the only drive i want to use going forward. It has old software on it that would be a nightmare to reinstall.

My problem is that, when viewing Disk Utility from the 920gb partition, the "-" button on the 80gb partition is greyed out so i can't delete it. And i can't resize it down, only up. Not sure how to proceed.

partition.png


I have a 1TB external HD that i could use to aid this process if necessary, but i'd prefer to explore alternate options that don't involve formatting the drive etc, because A) the external is currently getting used for an older SL backup that i'd like to keep if possible (although it's not absolutely imperative, spose i could update the external to host my current El Capitan 920gb since the old software still works on Capitan fine), and B) it makes me a little nervous lol.

Both drives are running OS X 10.11.6.

Also note that i'm considering upgrading to Sierra along the way (slightly worried my licenses wont carry over? Also El Capitan has good stability for my 32bit software right now). Just a minor note, in case that gets worked into the strategy somewhere.

Thanks for any help!
 
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mikehalloran

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Oct 14, 2018
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You know that you cannot have two OS on the same partition, right?

This is easily done in Disk Utility. You will lose all data on the partition that you are removing. Make sure that everything is properly backed up.

Move all data you want to keep onto the main partition. If you do not have the room, you will need to move it onto an external. Back up everything again — Time Machine is fine but it will take awhile to run since you've moved files around.

In Disk Utility, you will now expand the main partition and erase the second. Many web sites spell out the steps so I won't. It's also fairly intuitive.
 

Barncore

macrumors newbie
Original poster
Oct 7, 2014
27
0
You know that you cannot have two OS on the same partition, right?

This is easily done in Disk Utility. You will lose all data on the partition that you are removing. Make sure that everything is properly backed up.

Move all data you want to keep onto the main partition. If you do not have the room, you will need to move it onto an external. Back up everything again — Time Machine is fine but it will take awhile to run since you've moved files around.

In Disk Utility, you will now expand the main partition and erase the second. Many web sites spell out the steps so I won't. It's also fairly intuitive.
I've spent the past hour googling and reading. As i said, i can't expand my main partition or erase it because the minus button is greyed out

Note: I want SL 10.6.8 to be my main
 

macpro2000

macrumors 6502a
Apr 20, 2005
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You're making this way too hard by not wanting to reformat...just move it all over, format the original into one and clone it back with Carbon Copy Cloner. Easy.
 
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mikehalloran

macrumors 68000
Oct 14, 2018
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The Sillie Con Valley
You're making this way too hard by not wanting to reformat...just move it all over, format the original into one and clone it back with Carbon Copy Cloner. Easy.
Agreed. You are making way it too complicated.

Note: I want SL 10.6.8 to be my main
Yes but you also want it to work a certain way that it won't.

It's probable that Disk Utility won't let you go backwards. You must erase the drive.

Because it's OS 10.6 it might not be as simple as clone and back.

From the SL partition, Clone into your external.

Boot from the external, run Migration Assistant and see if you can pull your work files over — no system files or applications—from your El Cap drive. If it lets you, great as it will save you permissions errors and you can ignore the next paragraph.

If Migration Assistant won't work, zip/archive/compress your Documents/Music etc., move the folders over and expand onto the same folders in the new drive. After you've done so, delete the zip files to make room. This is time consuming as hell but certain file types will not open properly if not done this way. If Migration Assistant works, this isn't an issue.

Now reinstall any apps you need from the El Cap partition — if you can — some may not want to work over SL.

Once you have your SL external set up exactly the way you want it, now you can clone it back to your internal if it will let you. If not, run Disk Utility from the external and reformat the internal. Try again.

If that still won't work, I know what to do next but it should work.
 

Barncore

macrumors newbie
Original poster
Oct 7, 2014
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Agreed. You are making way it too complicated.

Yes but you also want it to work a certain way that it won't.

It's probable that Disk Utility won't let you go backwards. You must erase the drive.

Because it's OS 10.6 it might not be as simple as clone and back.

From the SL partition, Clone into your external.


Boot from the external, run Migration Assistant and see if you can pull your work files over — no system files or applications—from your El Cap drive. If it lets you, great as it will save you permissions errors and you can ignore the next paragraph.

If Migration Assistant won't work, zip/archive/compress your Documents/Music etc., move the folders over and expand onto the same folders in the new drive. After you've done so, delete the zip files to make room. This is time consuming as hell but certain file types will not open properly if not done this way. If Migration Assistant works, this isn't an issue.

Now reinstall any apps you need from the El Cap partition — if you can — some may not want to work over SL.

Once you have your SL external set up exactly the way you want it, now you can clone it back to your internal if it will let you. If not, run Disk Utility from the external and reformat the internal. Try again.

If that still won't work, I know what to do next but it should work.
As i said, the "SL 10.6.8" drive isn't OS 10.6 (it's just labelled that way), it's El Capitan.

I know it's a little confusing because of the misleading drive name, that's why i mentioned it multiple times for absolute clarity.
Here's my situation. I have a 1TB internal hard drive on my 12,2 iMac that, when i first got it, i split into 2 partitions. I got my refurbished imac shipped with El Capitan, but i wasn't ready to make the move from Snow Leopard yet since all my old music projects relied on the older software and plugins, so i made 1 partition 920GB to host my backed-up Snow Leopard system, and the other partition was 80gb so i could casually use El Capitan for a while and see if i liked it.

Fast forward almost 2 years and i finally upgraded my 920gb Snow Leopard drive to El Capitan (and all my software works fine), so now i have no i need for the 80gb El Capitan partition anymore, and i want the disk space. I just want 1 partition HD.

However there's software on the 80gb drive that i'd like to use on my final 1 drive too. So i'd like to either merge to the 2 partitions OR copy+paste data over to the 920gb and then deleting the 80gb partition.

Here's my setup...

The 80gb El Capitan drive is called "Macintosh HD". Or disk0s2:

(pic1)

^ I realize this drive is full. I can fix that if needed for functionality reasons?

The 920gb drive is called "SL 10.6.8". Or disk0s4. Despite the name, "SL 10.6.8" is running El Capitan as well (since today)...

(pic2)

^ This is the only drive i want to use going forward. It has old software on it that would be a nightmare to reinstall.

My problem is that, when viewing Disk Utility from the 920gb partition, the "-" button on the 80gb partition is greyed out so i can't delete it. And i can't resize it down, only up. Not sure how to proceed.

(pic3)

I have a 1TB external HD that i could use to aid this process if necessary, but i'd prefer to explore alternate options that don't involve formatting the drive etc, because A) the external is currently getting used for an older SL backup that i'd like to keep if possible (although it's not absolutely imperative, spose i could update the external to host my current El Capitan 920gb since the old software still works on Capitan fine), and B) it makes me a little nervous lol.

Both drives are running OS X 10.11.6.

Also note that i'm considering upgrading to Sierra along the way (slightly worried my licenses wont carry over? Also El Capitan has good stability for my 32bit software right now). Just a minor note, in case that gets worked into the strategy somewhere.

Thanks for any help!
That's the 2nd time you've overlooked detail in my post specific to my situation. I say this with all respect, pleeeeease read before giving advice. I'm not trying to be rude but i would love to be able to trust the advice, but it's hard if you're not reading what i'm saying.

Moving on.

If formatting/cloning is the only way to reduce my 2 partitions to 1 in my situation (is it though?), then i guess i'll go to my next question.

What's the best way to copy data from one El Capitan partition to another, including permissions and licenses etc? Is there a migration assistant for El Capitan?
More specifically, i'd like to be able to copy+paste plugins over from the 80gb partition to the 920gb partition. Maybe even software too if possible?
 

Barncore

macrumors newbie
Original poster
Oct 7, 2014
27
0
Mentioning it 3 times wasn't clear enough? Ok.

Maybe somebody else can chime in. I'm looking for the security of knowing i'm doing the right thing (for my particular set up and circumstanes) before i proceed.
 
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Fishrrman

macrumors P6
Feb 20, 2009
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OP:

Pay attention to what the guys have said above.

If you REALLY want to "clean up the internal drive" and make it 1 partition with "everything on it", you're going to have to do the following:

1. Use a cloning app (CCC would do best) to make a clone of the first partition to another drive (or partition on another drive). Then use CCC to make a clone of the second partition to another drive, as well. TWO cloned backups, one of each partition.

2. Pick the cloned backup that has the OS you want to keep on it.

3. Boot from the cloned backup you just chose. Get to the finder.

4. Open Disk Utility and ERASE your internal drive to Mac OS extended with journaling enabled.

5. Now the internal drive is returned to ONE [empty] partition. You have to start rebuilding it.

6. Quit DU and re-open CCC.

7. RE-clone the cloned backup BACK TO the new [single] partition.

8. Once done, boot from the internal drive, log in, look around, make sure things are ok.

9. Now you're going to have to "manually migrate" the stuff you want to keep on the "second" cloned backup (b/u of "the second partition") to the internal drive. Yes, it's going to be some work, but this is what you have to do.

10. IMPORTANT: BEFORE you start copying, you need to click ONE time on the icon for the "second drive". Then type command-i (eye) to bring up "get info". Then go to the bottom, click the lock and enter your password. Then put a check into "ignore ownership on this volume" (sharing and permissions). This prevents "permissions problems" with any copied files or apps.

This should "get you where you want to go".

It doesn't matter if you "don't want to do this".
The process above will take some time, but isn't really difficult.
Sometimes a man's gotta do.... what a man's gotta do.
 
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Barncore

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Original poster
Oct 7, 2014
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Ayyy Fishrrman. You helped me a bunch in another topic a few months ago. I can trust you.

Thanks for laying out the steps.

10. IMPORTANT: BEFORE you start copying, you need to click ONE time on the icon for the "second drive". Then type command-i (eye) to bring up "get info". Then go to the bottom, click the lock and enter your password. Then put a check into "ignore ownership on this volume" (sharing and permissions). This prevents "permissions problems" with any copied files or apps.
That's a gold nugget piece of info right there. Thanks a bunch.

See, this is why i came here before proceeding.

Quick question. I'm considering doing some disk cleanup, such as defrag and some Onyx things (no idea how to use Onyx yet though). Would you say it's better to do that before or after restoring back onto new partition?

Or is defragging on Mac hard drives a myth? I've heard some people say that. My HD is not solid state though.

If there are any other good measures/precautions like that to take then lemme know (cos i don't know what i don't know), otherwise i'm all set! Cheers
 

Fishrrman

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Feb 20, 2009
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If you "re-clone" to an empty volume from a backup, chances are the internal drive won't be fragmented, as all the files get copied over "contiguously".

Defragging IS NOT "a myth". It's an essential process with platter-based hard drives (at least in some circumstances). This is particularly true for digital audio and video, which require large blocks of contiguous "free space" for uninterrupted recording (interruptions could happen if the write head has to "skip around" to find fragments of free space).

And "the free space" issue is "the other" reason to defrag now and then. Over time, a platter-based disk will not only acquire fragmented files, but "the space between the files" (i.e., "the free space") will become fragmented, as well.

All you have to do to see this is "look at the disk" with an app that shows you files and fragmentation.

Having said that...
What I would do in your case:
Run Onyx on your backups BEFORE you "restore them".
Do the erase/restore.
Then... check for fragmentation. If there's only a little, don't bother.
Otherwise, degrag if needed.
 
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Barncore

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Original poster
Oct 7, 2014
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I'm about to backup my system and restore it onto my formatted internal. Quick question.

As a rule, is it generally advisable (for the goal of better HD health going forward) to delete any unwanted software before or after restoring back onto the internal?

Ideally i'd like to leave old school apps on the backup for the sake of always having it there after i delete them from the internal (just in case i need it + just in case i delete something that is essential for something else to work), BUT maybe my internal HD would be healthier if i didn't restore a system on it that has a lot of bloat and unused apps?

Or is it irrelevant, as long as i defrag after i'm finished restoring?

I've been using this system since like 2011 so there is a lot of old apps i don't need. Trying to figure out best time to delete them. Thanks
 

Fishrrman

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Feb 20, 2009
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Get rid of the "unwanted stuff" BEFORE you do "the backup, erase, and restore".
Things will go better that way.

If you have apps that YOU KNOW YOU DON'T WANT any more, I suggest the free utility called "App Cleaner".
How it works:
1. Open App Cleaner
2. Open your Applications folder in the finder
3. Drag the app icon you want to delete and drop it into App Cleaner
4. App Cleaner will "look around" and gather all the components of that app, and present them to you in a window with a "remove" button at the bottom
5. Click "remove" and they go into the trash
6. Empty the trash
7. Done.

And remember, the BEST way to do what you want to do is to create a BOOTABLE CLONED BACKUP using either CarbonCopyCloner or SuperDuper.
Then... boot from the cloned backup and erase the internal drive (to 1 partition, right?)
Then... RE-clone the cloned backup BACK TO the internal drive.
 
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Fishrrman

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Feb 20, 2009
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I have to disagree, Mike.

I've used App Cleaner now and then, and it works "just as advertised" for my needs. But "my needs" may be different than yours.

Regarding Adobe... can't say... I don't use their products.