Boot Volume missing, command line help

honeycombz

macrumors 6502
Original poster
Jul 6, 2013
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hey, I could use some help with some command line boot volume troubleshooting help. I'm on an iMac 5k and I won't go into the details but updated some software that I suspect changed the boot volume Name, or user folder name, or id. Too long to get into the details but I have a legit hunch. Anyhow, now I am getting the circle with slash icon and when I boot from a separate USB boot volume only see a drive in disk utility... no partition or anything. When I run disk repair it spits out

"Incomplete or Inconsistent CoreStorage Physical Volume"

What I am looking to do is run some diskutil list type commands to get you guys info you need to shed more light on the problem in hopes someone can help me navigate my way via command line to edit whatever needs to be edited to fix this.

Clear as mud? :)
 

casperes1996

macrumors 603
Jan 26, 2014
5,308
3,132
Horsens, Denmark
What I am looking to do is run some diskutil list type commands to get you guys info you need to shed more light on the problem in hopes someone can help me navigate my way via command line to edit whatever needs to be edited to fix this.
Well let's start with the diskutil list you point out yourself, and then also "diskutil cs list" for the core storage information.You don't have access to another Mac or Linux computer you can run GDisk from do you?
 

honeycombz

macrumors 6502
Original poster
Jul 6, 2013
481
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I am attaching a screen of some basic info (most is probably redundant) that will hopefully provide a better sense of what I'm dealing with. It seems like the SSD from the fusion group is the only thing it picks up? And that the main drive is missing?
 

Attachments

casperes1996

macrumors 603
Jan 26, 2014
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Horsens, Denmark
I do have access to another mac. How would I run GDisk?
You need to download and compile it. It's for manipulating partition maps. though I don't think it'll be useful after reading your second post.

I am attaching a screen of some basic info (most is probably redundant) that will hopefully provide a better sense of what I'm dealing with. It seems like the SSD from the fusion group is the only thing it picks up? And that the main drive is missing?
That does seem like your HDD is missing entirely. As of right now, the only thing I can think of, is un-fusing the Fusion Drive, and only using the SSD for now
 

honeycombz

macrumors 6502
Original poster
Jul 6, 2013
481
119
I think this was a 2015 iMac 5k (not positive on the yeae) 17,1. I wonder if some cheap seagate drive inside just totally failed. Maybe I should check out if there are any recalls. From the disk utility though it seems like the partition map is just messed up. Which Diskwarrior could fix, if it could see it. I mean, this doesnt even seem like a restore from backup situation does it? The hd is mia.
 

casperes1996

macrumors 603
Jan 26, 2014
5,308
3,132
Horsens, Denmark
I think this was a 2015 iMac 5k (not positive on the yeae) 17,1. I wonder if some cheap seagate drive inside just totally failed. Maybe I should check out if there are any recalls. From the disk utility though it seems like the partition map is just messed up. Which Diskwarrior could fix, if it could see it. I mean, this doesnt even seem like a restore from backup situation does it? The hd is mia.
What cannot be detected cannot be restored from a backup, so yeah
Don't think it's just the partition map though, as with a Fusion Drive setup, diskutil list should show three separate disks - The HDD, the SSD and the Core Storage volume that combines them. Now if the Core Storage volume gets corrupted you can still recreate it and be fine, but what seems to have happened to you is that the entire disk of the HDD is gone, along with it half of the Core Storage volume, meaning you can't even access the Core Storage partition map, which is what macOS would see if you tried talking to it on a booted system. You could mess with the partition map on the SSD, but you can't see the HDD and therefore not communicate with it. One thing you can try is booting the Mac in Target Disk mode and see if another Mac can detect anything, but it's highly unlikely.
 

chrfr

macrumors G3
Jul 11, 2009
9,877
3,690
I think this was a 2015 iMac 5k (not positive on the yeae) 17,1. I wonder if some cheap seagate drive inside just totally failed. Maybe I should check out if there are any recalls. From the disk utility though it seems like the partition map is just messed up. Which Diskwarrior could fix, if it could see it. I mean, this doesnt even seem like a restore from backup situation does it? The hd is mia.
It definitely appears to me that the spinning disk part of your Fusion Drive has failed. It's extremely unlikely that this has anything to do with any software you installed.
 

honeycombz

macrumors 6502
Original poster
Jul 6, 2013
481
119
Looks like this machine is under warranty for another month and I have a backup that is less than a week old. What a pain. Friggin iMacs. Bring back the Mac Pro so I can swap out drives in ten seconds.
[doublepost=1490624963][/doublepost]Will Apple give me back my busted drive so I can at least look into it easier? Any last ditch efforts here? Reseat the RAM? I haven't run AHT yet. Maybe I will try that. If it's even loaded on this thing.
 

casperes1996

macrumors 603
Jan 26, 2014
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Will Apple give me back my busted drive so I can at least look into it easier? Any last ditch efforts here? Reseat the RAM? I haven't run AHT yet. Maybe I will try that. If it's even loaded on this thing.

I doubt you'll get the drive from Apple at all. You can un-fuse it and have access to the SSD, but do the warranty thing since only having the SSD and not the HDD would be a shame.
RAM has nothing to do with this at all.
AHT has been replaced with Apple Diagnostics on new machines which doesn't vie much information usable to you, but instead says "Take it to an Apple Store", and then information only they can use.
My guess is that the SATA cable connecting the drive has come loose somehow
 

honeycombz

macrumors 6502
Original poster
Jul 6, 2013
481
119
Lol @ Apple Diagnostics > take it to the Apple Store. Times have changed.
[doublepost=1490629211][/doublepost]It's funny how my iMac 9,1 still kicking with factory drive. That thing must be a 2009 I think. This one is a 2015 refurb. The 5ks are probably lemons. Subtle lemons.
 

honeycombz

macrumors 6502
Original poster
Jul 6, 2013
481
119
Just ran Apple Diagnostics. Took less than two minutes. "There may be an issue with your storage device".

Wow.
 

casperes1996

macrumors 603
Jan 26, 2014
5,308
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Horsens, Denmark
Just to confirm: is there anything here worth looking into?
Not at all related to your isse. This would be relatively easy to fix if this were the problem (and could be fixed by aforementioned GDisk). Your issue is not a partition, but an entire disk not showing up, meaning we can't talk to the disk either.
 

honeycombz

macrumors 6502
Original poster
Jul 6, 2013
481
119
Guess it’s off to the Apple Store. I will report back when I find out what was wrong. Does seem like the SATA cable could be suspect since this computer showed none of the preliminary symptoms of one that was about to fail but I suppose sometimes drives just die. Especially cheap Seagate trash.
 

Weaselboy

Moderator
Staff member
Jan 23, 2005
30,609
10,396
California
Just ran Apple Diagnostics. Took less than two minutes. "There may be an issue with your storage device".

Wow.
Just for grins... try this. Command-option-r boot to recovery and you will see a spinning globe while the recovery utility downloads. Once you get to recovery open Terminal from the Utilities menu up top and enter the command below exactly like I have it. That will blow off the Fusion drive and all your data (hopefully you have a backup).

Code:
diskutil cs delete "Macintosh HD"
Then start Disk Util and tell us if you can see both drives?
 

Weaselboy

Moderator
Staff member
Jan 23, 2005
30,609
10,396
California
Good idea to try it out. Didn't even think to suggest it since I think if it would work, he would already be able to see both drives right now - but better try than not :)
Yeah... I figured it can't hurt to try at this point. I was thinking if the second drive is stuck somehow partly fused (<I made that word up :)) it might keep it from showing up.
 

casperes1996

macrumors 603
Jan 26, 2014
5,308
3,132
Horsens, Denmark
Yeah... I figured it can't hurt to try at this point. I was thinking if the second drive is stuck somehow partly fused (<I made that word up :)) it might keep it from showing up.
Even if that's the case, I would imagine that deleting the Core Storage container would only be able to delete the bit on the SSD and not the HDD, since it would have as little ability to access it as diskutil list – But let's see if it helps. It would be great if it did
 

honeycombz

macrumors 6502
Original poster
Jul 6, 2013
481
119
Already with the Genius Boys. Will see what they have to say. They said they would check both the cable and the drive.
 
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