HDD Corrupted and Cannot Erase/Restore

[rayward]

My mid-2010 iMac, running High Sierra, crashed and won’t recover. It won’t boot unless in recovery mode, but I can do very little in that mode. I ran First Aid and got an all clear on both the SSD & HDD, but the HDD part of my fusion drive reads as full, when it was only just over half full before, so there’s definitely something wrong there. The HDD is also described as “uncounted”.

I cannot erase the drive using Disk Utility, that option is greyed out. It won’t recognize my Time Machine backup to restore from there. It won’t find a disk for me to reinstall the OS. I don’t have a boot disk/drive.

Ummm...help?!!

 

[theapplehead]

When you’re in recovery mode, go to Disk Utility. After that, you must select “View All Drives” (under the view option I think but I can’t remember for certain?). Then select your main drive, the one at the top, and select erase. And lastly make sure the format is set to GUID. If that doesn’t work, then I’d suggest contacting Apple.

Good luck!

 

[Fishrrman]

This is why a savvy Mac user always ALWAYS ALWAYS keeps an external FULLY-BOOTABLE to the finder drive handy.

Because... what happens if you get into an "I can't boot" moment?
Which is where you are right now.

So... where do we go from here?

It's possible that your internal platter-based HDD may have failed, while the internal SSD portion of the fusion drive still works, but "is full" -- so full that it won't boot any more.

You need to create an external fully bootable drive.
We can do that.

Do you have an extra drive around?
DON'T use your TM backup -- you may need it.
It could be a USB hard drive.
It could even be a USB flashdrive (but has to be 32gb or larger).

Here's what to do:
1. Boot to recovery mode
2. Connect the external drive and use Disk Utility to erase it Mac OS extended with journaling enabled.
3. Quit DU and open the OS installer
4. Start the OS installer, but when it asks WHERE to install, AIM IT at the external drive
5. See if the installer will install a copy of the OS onto the external drive. It will take a while, and may involve a reboot or two
6. When done, you will be presented with a setup screen that looks like it would on any new Mac.
7. Set up a basic account. Can you get it to the finder?

If so, you now have your "Second bootable-to-the-finder" drive.
When you get to the desktop, can you see the internal fusion drive on the desktop?
Can you open Disk Utility, and see it that way?
The idea is that being booted externally, you can now do things you couldn't otherwise do from only the recovery partition.

Try this and get back to us.

 

[rayward]

Thanks Fisherrman. I created a USB boot drive, and got my Mac to boot into it. That allowed me to see and erase the SSD and HDD, but now I’m stuck trying to get them re-fused.

I know how to do it, but when I boot into recovery mode off the USB drive, it won’t recognize my wireless keyboard or track pad. I installed the OS on the SSD and everything is fine, but I can’t create the fusion drive when booted from one of the drives to be fused.

There are chickens and eggs running wild here right now.

 

[rayward]

Update: I booted into internet recovery mode and fused the drives but the install of OS X fails. As I’d already got the OS to install on the SSD on its own, it has to be the HDD.

 

[Fishrrman]

"I booted into internet recovery mode and fused the drives but the install of OS X fails. As I’d already got the OS to install on the SSD on its own, it has to be the HDD."

OK, if one way doesn't work, we can try another way.
PRINT THIS MSG OUT AND KEEP IT FOR REFERENCE.

Do this:
1. You're going to need CarbonCopyCloner. It's FREE to use for 30 days, so doing this will "cost you nothing". You DO need to download the correct version for the OS that you're using (which OS is it?).
You can download CCC from here:
http://www.bombich.com/download.html
(older versions are available if you need them)

2. The internal fusion drive is again "fused", right? OK, then do this:

3. One more time, BOOT FROM the EXTERNAL USB boot drive that you created.
Umm... just to be sure... this drive is "bootable to the finder"?, or is it a bootable installer drive?
To do what I describe next, the drive needs to be bootable to the finder.

4. Put a copy of CCC onto the external USB drive. Open CCC.

5. Accept all CCC's default settings for now.
Put the source drive (the USB drive) on the left.
Put the destination drive (the internal fusion drive) "in the middle"
Don't worry about "schedule".
Click the clone button, and then the "run now" button (if required).
The clone will take a little while, be patient.

6. WHAT YOU ARE DOING:
CCC will clone the contents of the USB drive to the internal drive, which should give you a bootable copy of the OS on the internal fusion drive.

7. What to do next:
When done, quit CCC and open the Startup Disk preference pane.
Click the lock and enter your password, then select the internal fusion drive to be the boot drive.
Now, power down -- ALL THE WAY OFF.
Disconnect the USB drive.
Wait a few seconds, then press the power-on button.
Do you get to the login screen?
Can you login?

Try this and get back to us.

 

[rayward]

Thanks for the follow-up, but CCC couldn’t see the drive at all. I figured it was time to give up on the HDD; it had already been erased so there was no data to save.

The replacement (larger) HDD was here, so I popped that in, fused it with the SDD and I’m currently installing the OS. After that, it’s time to pray the Schrödinger's backup is found alive when I open its box.

 

[rayward]

So here's where I stand: the new fusion is drive up and running perfectly, but I cannot get the backup to connect. I can access the backup drive from my network, but when I try to use Migration Assistant to reinstall from there, it finds the backup drive but says the backup isn't available, telling me to try again later or check my network connection (which is fine - it's ethernet between the Mac and the backup drive).

Any more help will be gratefully received.
[doublepost=1559527426][/doublepost]

Here’s the error message.

 

[Fishrrman]

Can't help with TM, I've never used it, ever.
And I don't recommend that others do so.
You're finding out WHY I make those recommendations right now.

What KIND of drive is the backup on?
Is it on a "regular, plain old drive" that you can connect via USB?
Or is this some kind of "NAS" drive, or something else?
WHERE is the drive?
Can you get it "right next to you", within arm's reach?

 

[treekram]

So here's where I stand: the new fusion is drive up and running perfectly, but I cannot get the backup to connect. I can access the backup drive from my network, but when I try to use Migration Assistant to reinstall from there, it finds the backup drive but says the backup isn't available, telling me to try again later or check my network connection (which is fine - it's ethernet between the Mac and the backup drive).

Any more help will be gratefully received.
[doublepost=1559527426][/doublepost]View attachment 840180 Here’s the error message.

I would check your network settings, but, if it can find the drive but not read it, hmmm ... I'm not sure exactly what to check.

So, maybe you need to take the disk and connect it directly to the computer. From what I've read, you would need to navigate and find a ".sparsebundle" file and double-click on it. Then, re-run the Migration Assistant. Or you if you can't find the file, just connect the disk and see if Migration Assistant can find it. There's more information at the following link:
https://apple.stackexchange.com/questions/341896/time-machine-backup-to-a-sparsebundle-on-usb-drive

 

[rayward]

The backup is on a Buffalo LinkStation NAS, but it is close enough to my Mac to connect it directly, if I am reading your thoughts correctly.

 

[treekram]

The backup is on a Buffalo LinkStation NAS, but it is close enough to my Mac to connect it directly, if I am reading your thoughts correctly.

Obviously, something is not going correctly with your restore. The presumption (hope) is that it's a networking issue of some sort vs. a disk issue. I presumed that you had a plain disk connected to the router, but obviously that's not the case. According to one website I saw, the Buffalo NAS (generic term, who knows if it applies to your specific hardware) will store the Time Machine in a sparse bundle. Now I don't know if the disk itself in the NAS can be connected to your computer, I'm guessing not (maybe the NAS itself can be but not the disk). If that's the case, I think you would be better off copying the sparsebundle file to an external disk, connect the external disk to your computer, mount the sparsebundle (double-click it) and then try Migration Assistant to see if it will find it. From what I'm seeing of the Buffalo NAS, it looks like you can navigate the NAS using the Finder, so the trick there is to find the sparsebundle that you want.

The bad news/good news is that if you're having network problems with the NAS, then you won't be able to copy off the sparsebundle file. If you can connect to the NAS and copy off the file, then it makes me wonder why it couldn't be found.

 

[rayward]

I can find the sparsebundle, but it has zero bytes.

 

[treekram]

In the Finder, right-click on the sparsebundle and see if you have read/write permission to it.

In looking on the Internet, just because it reports zero bytes doesn't necessarily mean it's zero bytes. If you have read permission, see if you can copy it. If it takes a while to copy, it's not zero bytes. Did you, by any chance, see the following message: "Time Machine completed a verification of your backups. To improve reliability, Time Machine must create a new backup for you."?

 

[rayward]

Getting the info on the sparsebundle, it shows two "(unknown)" users and "everyone" with read/write permission. I am logged in as "admin", and it won't let me copy the file - saying I do not have the necessary permission.

 

[treekram]

Getting the info on the sparsebundle, it shows two "(unknown)" users and "everyone" with read/write permission. I am logged in as "admin", and it won't let me copy the file - saying I do not have the necessary permission.

See if you can change the access permission on the network shared drive itself to the most permissive possible. If there's some Buffalo NAS utility, there might be something there to do that if you can't do it in the Finder.

From what I'm reading, one thing you shouldn't do at this point is try to do anything to repair the file or drive so try to get the permission issue sorted. If are able to change the permission for the network drive, see if you can then copy the file.

 

[rayward]

I think the issue is that I’m trying to access the backup from - essentially - a new machine, so it’s not recognizing my MAC as it’s rightful owner.

 

[treekram]

I think the issue is that I’m trying to access the backup from - essentially - a new machine, so it’s not recognizing my MAC as it’s rightful owner.

That's certainly possible - but if (perhaps a big IF) you're able to copy the sparsebundle from the NAS to a HDD you can connect to your iMac, at least the NAS permission issue should go away (it looks like your error in our post #15 and perhaps #8 is because of this NAS permission issue).

 

[rayward]

First, let me say thanks to all in this thread who have offered help and advice. Sorry if I wasn't clearly appreciative before.

Now, where am I? It does look like NAS permissions is part of my problem. I have tried to fix that using the NAS' utility, but it's hard to tell because of problems with the sparsebundle. My credentials appear drop when I reboot, so I have to open the NAS utility and reconnect. I think this may be part of the issue when accessing the backup through Migration Assistant, as that logs you out before you can do anything else. My NAS shows up in MA, and I can force MA to find the actual backup, but it says I do not have permission to access the files. Until I have a working sparsebundle, though, I won't know if I this is an access issue or a corrupted sparsebundle issue.

Speaking of which, I have been able to get my backup mounted via Terminal - sending my login credentials through the script - and have been able to run diagnostics and repairs on it. Scarily, I got an "invalid node height (1)" error, which I understand his a hardware issue, but the process kept on running and claimed my sparsebundle to have been repaired. It even had heft - 5.5TB, which sounds about right vs. 0kb which it was before the repair.

After that, I tried to remove the rejection flags from the sparsebundle but, when I opened the plist, there was no sign of a "RecoveryBackupDeclinedDate" but the "VerificationState" integer was 1, not 0. I understand that the integer needs to be 0 but, when I tried to edit the plist, the NAS went into a frenzy of seemingly endless whirring and the edit script hung. When the NAS finally stopped whirring (hours later), the sparsebundle was back to 0kb.

I think I should have detached the Apple_HFS disk before trying to edit the plist, so I'm going to try again and not skip that part. Now I'm running the fsck again; got the node height error again; and it's completing the process the same as before. It ran through three times last time, and it takes a while.

So, for review and posterity, here are the scripts I've run:

sudo su -
to access the root directory

mkdir /Volumes/TimeMachine
to give me a place to mount the backup

mount_afp afp://<login>:<password>@<NAS-ip-address>/<backup folder name> /Volumes/TimeMachine
to mount the backup folder (it took me a long time to get that syntax correct, because the articles on the web assume a greater understanding of the lingo than I have, and Terminal doesn't like a punctuated file name so I had to rename my sparsebundle)

chflags -R nouchg /Volumes/TimeMachine/<backup filename>.sparsebundle
to reset any dirty flags

hdiutil attach -nomount -readwrite -noverify -noautofsck /Volumes/TimeMachine/<backup filename>.sparsebundle
to attach the actual sparsebundle

fsck_hfs -drfy /dev/diskXs2
to repair the sparsebundle, where "X" is the number of the disk with the Apple_HFS file, returned from the response to the prior command


So far, the do-over is following the prior pattern. Here's what I have so far:

Executing fsck_hfs (version hfs-407.50.6).
** Checking Journaled HFS Plus volume.
** Detected a case-sensitive volume.
The volume name is Time Machine Backups
** Checking extents overflow file.
** Checking catalog file.
** Rebuilding catalog B-tree.
hfs_UNswap_BTNode: invalid node height (1)
** Rechecking volume.
** Checking Journaled HFS Plus volume.
** Detected a case-sensitive volume.
The volume name is Time Machine Backups
** Checking extents overflow file.
** Checking catalog file.
** Checking multi-linked files.
** Checking catalog hierarchy.
** Checking extended attributes file.
** Checking multi-linked directories.

privdir_valence=240445, calc_dirlinks=993418, calc_dirinode=240445



FYI, the script I ran to check for bad markers was:
cd /Volumes/TimeMachine/<my-backup>.sparsebundle
vi com.apple.TimeMachine.MachineID.plist


So, when the fsck ends, I'm going to detach the Apple_HFS driver (hdiutil detach /dev/diskXs2), run the cd script to see if there are bad markers, deal with those as necessary, unmount everything and try and get into the backup through Migration Assistant.

There is still time to stop me...

 

[rayward]

Well the fsck process completed and I got the confirmation that my sparsebundle was repaired. I ran the script to check for bad markers and got the integer 1 error, which I edited to 0. I saved the plist, ejected the volume (using Finder) and went back to the Migration Assistant...which could not access my NAS.

I'm thinking now I still have permission issues. Ugh!

 

[treekram]

I was traveling yesterday so I didn't get the chance to respond to your post. It's good that you found references to fixing the sparsebundle issues and that you seem comfortable executing it. I still think you should have (and still should) copied off the sparsebundle off of the network to an external disk and then work on it. In doing some research on the web, I see that the sparsebundle isn't a single file, it's a directory with multiple files. Although if you copy it using the Finder, it appears as a single file.

 

[rayward]

I was traveling yesterday so I didn't get the chance to respond to your post. It's good that you found references to fixing the sparsebundle issues and that you seem comfortable executing it. I still think you should have (and still should) copied off the sparsebundle off of the network to an external disk and then work on it. In doing some research on the web, I see that the sparsebundle isn't a single file, it's a directory with multiple files. Although if you copy it using the Finder, it appears as a single file.

I'm not sure if it's because of - or despite - my fooling around in Terminal, but my sparsebundle is currently moving to my Mac. The move, rather than copy, was in error, but I didn't want to try and stop it because it's actually doing something. Copying it to another external drive wasn't an option anyway, due to the file size. My hope is that, once it's on my Mac, I will be able at least to extract files from it.

I don't need to restore the whole thing (although that would be nice), but I do need to get files out of it such as apps, photos and docs. I have read that it's possible to open the sparsebundle and extract files, so, my goal right now (but I'm open to suggestions/advice), is to extract what I need, get them installed on the clean OS I have now, delete the old sparsebundle, reformat the NAS and start a new TM backup.

All of this, of course, depends on what I find once the sparsebundle is on my Mac...

 

[rayward]

After spending 20 hours moving my sparsebundle, I go an error message saying it can't be moved because I do not have permission to access the file. Argh!

 

[Fishrrman]

I think there's a lesson to be learned here.

That lesson is:
DO NOT rely on NAS for backing up a single Mac.

Use a "dedicated external drive", connected through "normal" means (i.e., via USB, etc.).

Doing it this way should make recovery easier, if and when that "recovery" is needed.

And again...
I WOULD NOT "put my trust" in Time Machine, ever.
Use either CarbonCopyCloner or SuperDuper instead.

IF you had been using them, I'll reckon you would not be having these problems now.

 

[treekram]

With a sparsebundle size of 5.5 TB, that would require a HDD of 6TB (but better to have 8TB), which would not be cheap. If you can mount the sparsebundle on the NAS, you should see [computer name] and under that a "Backups.backupdb" folder which you can try copying to an external disk. Maybe that would not be so large as to require a major expenditure for a HDD (I bought a 8TB external drive some months ago for $129 and see that's still a pretty current price if it's on sale).

If whatever is in your backup is important to you, you should consider that the more work you do with the sparsebundle, the more likely it is that some irreparable damage will be done - either to the files or to the HDD in the NAS. That's why I keep suggesting copying the backup off the NAS before trying to work with it. At this point, maybe you can contact Buffalo or see if here's something on their support site with people having similar issues.