The replacement disk must be as big or bigger than the original

[Robert_Chandra]

Trying to replace a 4TB seagate harddrive with a Samsung 4TB SSD.

Trying to get the array started but I'm seeing the error "The replacement disk must be as big or bigger than the original.

 

After reading other posts I'm seeing that this may have something to do with the motherboard creating an HPA on the drive. I am running a Gigabyte motherboard. The drive is currently assigned as /dev/sdb. Looking at fdisk -l, I'm seeing all of my drives (all of them are 4TB) have 4000787030016 bytes, 7814037168 sectors.

 

The only thing that is obviously different between the new drive and the old drives is the Sector size and I/O size:

 

SSD:

Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes

HDDs:

Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes

 

Not sure if that matters though since the total bytes and sectors are identical.

 

hdparm -N on each of the drives all show the same results:

max sectors   = 7814037168/7814037168, HPA is disabled

 

I have the unassigned devices plugin and tried to format the drive to see if that would do anything. Formatted to XFS with the array still stopped (all of my drives are on XFS - Encrypted) but the error is still not fixed.

 

So as far as I can tell the total sectors and bytes are identical, HPA is disabled, yet the array still won't start because it thinks the new drive is too small. I'm stumped.

 

I'm not a Linux expert so you may need to walk me through commands like you're explaining to a newbie. Any ideas what might be going on here? Thanks!

 

[Robert_Chandra]

Ok another thing I found while digging through the forum is to try reiserfsck --check. Here's what that gives me:

 

reiserfsck --check /dev/sdb
reiserfsck 3.6.27

Will read-only check consistency of the filesystem on /dev/sdb
Will put log info to 'stdout'

Do you want to run this program?[N/Yes] (note need to type Yes if you do):Yes
Failed to open the device '/dev/sdb': Unknown code er3k 127

[JorgeB]

4 hours ago, Robert_Chandra said:

Trying to replace a 4TB seagate harddrive with a Samsung 4TB SSD.

Unraid formats disks with the partition starting on sector 64, SSDs are partitioned on sector 2048 (for performance reasons) so you can never direct replace a HDD with an SDD of the same capacity, would need to do it manually.

[Robert_Chandra]

5 hours ago, JorgeB said:

Unraid formats disks with the partition starting on sector 64, SSDs are partitioned on sector 2048 (for performance reasons) so you can never direct replace a HDD with an SDD of the same capacity, would need to do it manually.

Ok so I wire up the old HDD and the new SSD at the same time, copy everything from one to the other, remove the HDD, and then just leave Disk 2 as missing from now on? Or is there a way to remove Disk 2 from the array? Or have it start treating Disk 4 as Disk 2 from now on? If I replace more of the HDDs and now I’ve got a 4 5 and 6, would all of 1 2 and 3 be missing forever or can I get the array to treat 4 5 and 6 as 1 2 and 3, etc?

[itimpi]

You can use the New Config tool which is covered here in the online documentation accessible via the ‘Manual’ link at the bottom of the GUI or the DOCS link at the top of each forum page to rearrange your drives.

[Robert_Chandra]

Stuck on the new drive being "Unmountable".

Running a filesystem check now, with the -n:

 

Phase 1 - find and verify superblock... bad primary superblock - bad magic number !!! attempting to find secondary superblock...

 

I'm assuming my next step is to run the filesystem check without the -n?

[itimpi]

22 minutes ago, Robert_Chandra said:

Stuck on the new drive being "Unmountable".

Running a filesystem check now, with the -n:

 

Phase 1 - find and verify superblock... bad primary superblock - bad magic number !!! attempting to find secondary superblock...

 

I'm assuming my next step is to run the filesystem check without the -n?

Was that running from the GUi or the command line?   Is a secondary super block found?

 

[Robert_Chandra]

9 minutes ago, itimpi said:

Was that running from the GUi or the command line?   Is a secondary super block found?

 

From the GUI, no change yet. Still stuck on the same "attempting to find secondary superblock" line.

[itimpi]

9 minutes ago, Robert_Chandra said:

From the GUI, no change yet. Still stuck on the same "attempting to find secondary superblock" line.

Ok - that means the correct device name would be selected .   I assume you are now getting dots displayed as the disk is searched for a secondary superblock.?

[Robert_Chandra]

2 minutes ago, itimpi said:

Ok - that means the correct device name would be selected .   I assume you are now getting dots displayed as the disk is searched for a secondary superblock.?

Yes. Also from the Main screen I can see the number of reads going up still. It's at 1,871,552

 

Is that referring to bytes or sectors or what? Because at this rate covering 4TB is going to take a while I'm thinking.

[Robert_Chandra]

1 hour ago, itimpi said:

Ok - that means the correct device name would be selected .   I assume you are now getting dots displayed as the disk is searched for a secondary superblock.?

I just did some math and if I'm reading this correctly, it should only take about 15 million reads to cover the whole drive. It's currently at about 5. So that means probably a couple more hours. Once it finishes and assuming it finds a second superblock, all I'd need to do is rerun the filesystem check without the -n correct? -n means it's just a test run?

 

If it doesn't find a superblock then what's my next step?

[Robert_Chandra]

3 hours ago, itimpi said:

Ok - that means the correct device name would be selected .   I assume you are now getting dots displayed as the disk is searched for a secondary superblock.?

After all that, all it said was "Exiting now." Sounds like it never found a superblock. So what's my next step for fixing the filesystem? There's no data on this drive.

[Robert_Chandra]

Actually good news. I'm not sure why this fixed it but after the file system check exited, I stopped the array, started it again, and now everything is mounted perfectly. So I might be good to go now. Copying files from disk 2 to disk 4.

 

Once the copy is done you were saying I can use the New Config tool to change the disk assignments? Is there any risk of me messing something up in that process and wiping out data? Or if you're willing to walk me through that I'd appreciate it.

[itimpi]

3 hours ago, Robert_Chandra said:

Once the copy is done you were saying I can use the New Config tool to change the disk assignments? Is there any risk of me messing something up in that process and wiping out data? Or if you're willing to walk me through that I'd appreciate it.

There is little that can go wrong if you follow the instructions in the link that I provided.  
 

The main thing when using Unraid is make sure you do not ever use format on a drive unless you intend to wipe its contents.

[Robert_Chandra]

I think I'm all set now. Thanks!