Caution - Yosemite may screw up partitions.

[BrooklynAl]

Checksum errors

As predicted, when I loaded Yosemite on an external hard drive I got another checksum error....if there are any "new contributors" that may shed light on this it would be appreciated. Clearly, this thread as an ample number of acolytes.........new blood recruited.

Here is an article by Ars Technica that discusses volume changes to main HD when loading Yosemite:

http://arstechnica.com/apple/2014/10/os-x-10-10/2/

 

[macenied]

As predicted, when I loaded Yosemite on an external hard drive I got another checksum error....if there are any "new contributors" that may shed light on this it would be appreciated. Clearly, this thread as an ample number of acolytes.........new blood recruited.

Here is an article by Ars Technica that discusses volume changes to main HD when loading Yosemite:

http://arstechnica.com/apple/2014/10/os-x-10-10/2/

How about ASKING People, whether they want to convert to core storage or not, just 3-5 code lines away ? Many users have a reason why they don't want to convert, mainly based on Apples artificial restrictions when it comes to Windows.

It's boring, really and it's getting rediculous. But Apple has never been good in asking the customer base, they seem to know that baybying customers is one of their priority tasks. Let's see how this will end up. For me it's just another step away from the Apple "ecosystem", not more, not less.

 

[BrooklynAl]

Not interested

How about ASKING People, whether they want to convert to core storage or not, just 3-5 code lines away ? Many users have a reason why they don't want to convert, mainly based on Apples artificial restrictions when it comes to Windows.

It's boring, really and it's getting rediculous. But Apple has never been good in asking the customer base, they seem to know that baybying customers is one of their priority tasks. Let's see how this will end up. For me it's just another step away from the Apple "ecosystem", not more, not less.

Big Smile.......

 

[grahamperrin]

… Apple has never been good in asking the customer base …

There's plenty of recent and less recent evidence to the contrary.

I distinguish between (a) requesting feedback, and (b) Apple acting upon that feedback.

I suspect that at a very high level – not within the Apple areas where feedback is received – certain use cases are wilfully ignored; customer feedback on problems in certain areas is ignored; and so on. Before Yosemite, I never had that suspicion.

 

[nospamboz]

Bad CS convert still in 10.10.1

On a mid-2009 Macbook running Mavericks 10.9.5, no AES, no Filevault, no place for a Recovery partition on the system disk due to multiboot (OS X, Linux, Windows). Yosemite 10.10.1 fresh installs to an external disk fine (normal HFS+, no CS). Trying to upgrade system, though, yields:

This partition map modification would make a Windows partition unbootable.

So it tried to convert to Core Storage, in spite of the fact that the install log contains this line:

Dec 24 10:04:42 localhost OSInstaller[430]: Won't convert to CS, CPU doesn't have AES instruction set

I also like this "upsell" honesty from the install log:

Dec 24 10:35:00 localhost Setup Assistant[197]: Skipping FDE upsell, CPU doesn't have AES instruction set
Dec 24 10:35:00 localhost Setup Assistant[197]: No iCloud user, skipping iCloud Drive upsell

I'm convinced there's a bug in the Yosemite installer, trying the auto-convert to CS when it shouldn't. I doubt it will be a priority for Apple to fix, though, because my guess is that people like me who can't use CS aren't potential customers for Apple's upcoming bootable encrypted extensible cloud drive service, or whatever.

At least Mavericks works.

 

[AndreSt]

I don't know why the installer does actually some volumes to Core Storage. But on my Mac mini 2014 this didn't happen:

Dec 10 10:04:05 localhost OSInstaller[399]: Won't convert to CS, machine is not a portable

Obviously the conversion to Core Storage will be only done on portable devices.

 

[grahamperrin]

Checks

… I'm convinced there's a bug in the Yosemite installer, trying the auto-convert to CS when it shouldn't. …

I don't see a bug.

As I see it, something (or some combination of things) performs checks, to tell whether conversion should occur.

 

[twocopper]

search for simple advice

Hi - in simple terms - I have very little experience dealing with the details of the details discussed in some parts of this thread but

I have 1 hard drive in 3 partitions and without obvious cause I now have suddenly found via disk utility that I have 2 LVG 's with different names -
1 containing 1 partition as named.
1 containing 2 partitions as named.

I m not greatly experienced as to the in s and outs of these types but now on trying to repair disk or disk permissions recieve the message - " Unable to unmount volume "

I have read through the thread here and will attempt terminal commands to revert to previous state , i.e. "Journaled HFS " , however I was looking for any further advice ofn the specifics , especially as I seem to have doubled the recognisable hard drive states .... i.e. now 2 named LGV visible on one physical drive .

oh - I have two different states of yosemite running on two of the partitions .


/dev/disk0
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *640.1 GB disk0
1: EFI EFI 209.7 MB disk0s1
2: Apple_CoreStorage 249.0 GB disk0s2
3: Apple_Boot Recovery HD 650.0 MB disk0s3
4: Apple_CoreStorage 194.5 GB disk0s4
5: Apple_Boot Recovery HD 650.0 MB disk0s5
6: Apple_HFS cart 3 195.0 GB disk0s6
/dev/disk1
#: TYPE NAME SIZE IDENTIFIER
0: Apple_HFS Cart 1 *248.6 GB disk1
Logical Volume on disk0s2
EBA428F1-7C77-477B-91A2-BAFB36EA3EEC
Unencrypted
/dev/disk2
#: TYPE NAME SIZE IDENTIFIER
0: Apple_HFS cart 2 *194.1 GB disk2
Logical Volume on disk0s4
DF3BEBDF-90F0-4D9D-9E71-48B15637F00E
Unencrypted

 

[nospamboz]

I'm convinced there's a bug in the Yosemite installer, trying the auto-convert to CS when it shouldn't.

OK, I managed to get Yosemite 10.10.1 to install by playing with Core Storage. Not for the faint-hearted.

1) In Mavericks, run "disktuil corestorage convert /" to force a conversion of the OS X volume to Core Storage. Multiple reboots are required to finish the process.

2) Boot off external Yosemite install disk, and install. It finally works, but creates a Recovery partition from the space made by shrinking the OSX partition, so the partitions went from "EFI, OSX, Linux, Windows" to "EFI, OSX, Recovery, Linux, Windows".

3) Booted into Yosemite, ran "diskutil corestorage revert /" which got rid of corestorage stuff after a reboot.

4) Booted off external Linux disk to run gparted and delete the Recovery partition.

5) Booted into Yosemite and ran "diskutil resizeVolume OSXpartition R" to reclaim the former Recovery area.

6) Rebooted Yosemite, and the partitions are as they were before the install.

Then reinstalled rEFInd, and all my multiboot options work as before!

I guessing this won't be an issue again until I need to upgrade to OS X 10.11, whatever that is. Hopefully they will have worked out the installer bugs by then. Meanwhile, hope this workaround helps people.

 

[twocopper]

search for simple advice- to previous post

terminal commands executed with no problems and two disk partitions returned to original state .

used "diskutil cs list" to source Logical Volume UUID.

used UUID for disk 1 and disk 2 separately with revert command-

"diskutil coreStorage revert lvUUID"

couple of seconds watching terminal feed playback info on process and disk partitions reverted to " Mac OS Extended (Journaled)".

Thankyou -

 

[randolorian]

I stumbled across an interesting LinkedIn profile that might shed a little light on this. It seems that Yosemite shipped with something called File Vault Everywhere (FVE in the installer log, I assume) that is distinct from File Vault 2. I bet this feature has a lot to do with Yosemite's automatic CS conversion. But I can't find any other info on this new feature.

Also, maybe old news, but it notes that ZFS buffer caching was dropped because of licensing issues with ZFS.

https://www.linkedin.com/profile/view?id=4436263&authType=name&authToken=O1NN&trk=prof-pat-cc-name

 

[BradHatter]

Why Core Storage on Yosemite

Some systems seem to install Yosemite as an unencrypted Core Storage volume when being put on a system. I can't figure out what the rules are for this, or why this is even being done. For example, if it's installed on one system it might retain its standard HFS+ GUID format without Core Storage, even if the drive has been erased. On others it seems to convert the volume to Core Storage.

Does anyone know why this is being done and what parameters are used during the installation process to determine when and why a volume with install as Core Storage.

The only way that I seem to be able to manage these volumes is by the command line.

 

[simonsi]

The only way that I seem to be able to manage these volumes is by the command line.

Correct, DU can't manage any Core Storage volumes on the drive on which your Yosemite partition is installed.

Best thing to do if you want to retain DU ability is to revert the CS volumes to standard HFS once the installation is completed, and in any case prior to enabling FV2 as once FV2 is enabled the CS volumes cannot be reverted.

I have NO idea why Yosemite converts partitions to a format the OS' own DU can't manage....

 

[leman]

Core Storage is the future of Apple's storage, I guess they are experimenting with some stuff on the large scale with Yosemite. It is certainly an oversight that Disk Utility has not been updated to handle Core Storage volumes, but Apple's management of OS X does seem somehow messed up lately. I hope they get back to the attention to detail they have been renowned for.

 

[grahamperrin]

Limitations of Disk Utility

… The only way that I seem to be able to manage these volumes is by the command line.

In Ask Different: What techniques for disk, volume and file system management are possible with OS X, but troublesome within Disk Utility?

Answers include:

• Management of some types of partition becomes impossible with the Partition tab

 

[simonsi]

Core Storage is the future of Apple's storage

Yes I appreciate that but a huge oversight, it was quite annoying - I have an SSD with 1 partition (other than recovery), on which Yosemite was first installed, it was converted to Core Storage which I reverted.

Then I installed it onto my 1TB HDD in a backup bootable partition as one of 2 partitions (other than recovery), of course during this install it converted the entire 1TB drive to Core Storage and both partitions...most rude given no available management utility...

 

[Weaselboy]

Does anyone know why this is being done and what parameters are used during the installation process to determine when and why a volume with install as Core Storage.

Some members in this thread have pieced together the answer to your second question. It seems to be:

1. Machine is a portable
2. CPU supports AES
3. No Bootcamp partition present

Then you get converted to core storage at Yosemite install.

Now as to why, I think everything to this point is just speculation since Apple has not said why.

 

[TheBSDGuy]

My suspicion is that they may want to be able to attach network shares as volume extensions, probably via iCloud.

 

[KoolAid-Drink]

Does the fully downloaded 10.10.2 installer resolve the automatic conversion, or is it still happening?

 

[simonsi]

It seems to be:

1. Machine is a portable
2. CPU supports AES
3. No Bootcamp partition present

Yep I fit those....

 

[grahamperrin]

Ot: Zfs

… ZFS buffer caching was dropped …

Please see https://forums.macrumors.com/showthread.php?p=20668232#post20668232

 

[AndreSt]

Does the fully downloaded 10.10.2 installer resolve the automatic conversion, or is it still happening?

Yes it does, it's actually one of the last steps of the installation.
The CS should still be revertable according to "diskutil cs list".

 

[Mike Boreham]

Does the fully downloaded 10.10.2 installer resolve the automatic conversion, or is it still happening?

Not sure what you mean quite.

The full 10.10.2 full installer still automatically converts to corestorage if the criteria are met, but you can still revert afterwards (I assume) if you want.

 

[BradHatter]

Can someone tell me what the Apple_Boot partition is? I've tried creating some Core Storage units, and every time i do so, it creates an Apple_Boot partition that's named "Boot OS X" and has a size of 134.2MB (M as in Mega). This is not a recovery partition. Recovery partitions are labelled "Apple_Boot" as well but have a size of 650 MB. A recovery partition will show up if I try to boot the system holding the "alt" key down and if I select one, it will put the system into recovery mode. None of the Core Storage created Apple_Boot sections show up at all.

 

[e93to]

I also noticed this on my iMac today. Yosemite partition is now the core volume...

My late-2012 iMac is on 10.8.5. Could the change in core volume harm the main start-up volume in any way? (corrupting files, changing core settings, making certain things now work, etc.)

Also, does this affect how Time Machine backs up the core volume?

Thanks.