Couple of days ago I replaced a drive that had errors. I had to remove all the drives to get to the 1 drive so that meant moving cables sata and power cables a bit. Nothing crazy.

I installed the new disk and began to rebuild it. As it started another disk had shown errors. I waited for the rebuild to finish and once it finished my parity drive began to show errors.

After some googling I'm guessing I have a cable issue meaning some cables may have been damaged or something during the moving.

I am awaiting new cables but at the moment one parity drive is working the second has errors the drive that second drive that needed to be replaced I tried it in another pc just to check the drive seems fine. I didn't want to format it because of the parity failure.

Now parity is rebuilding but without a drive.

So -1 Parity drive

-1 data drive

2nd parity drive is rebuilding.

Ordered new cables for the hba card and some new power cables. Also have another drive on the way for the last data drive.

Looking for suggestions of operations here. Parity should be done in 2 days. Should I wait for parity to finish? I'm wondering if that missing disk is still being emulated. I have the missing disk and it has data on it so I may not be totally screwed. Should I stop the parity and shut down and fix all the cables and see if I get no errors back?

Thank you for any and all info.

Are you using power splitters? Try to avoid or limit splits as much as possible. If replacing cables and do not do it, it could be your psu. Keep in mind that during parity check, all the drives run simultaneously so thats when most power draw happens.

14 minutes ago, Cor4eyh said:

Should I wait for parity to finish?

You should not have started a rebuild on a broken array. Get your drives working before you run a new parity check.

Please post the diagnostics.

Here are the diags

tower-diagnostics-20260413-1105.zip

21 minutes ago, Veah said:

Are you using power splitters? Try to avoid or limit splits as much as possible. If replacing cables and do not do it, it could be your psu. Keep in mind that during parity check, all the drives run simultaneously so thats when most power draw happens.

You should not have started a rebuild on a broken array. Get your drives working before you run a new parity check.

I forgot to mention in my post that everything was Gucci after installing the replacement drive. Upon finishing rebuild the second drive failed. I thought it was a bit crazy but not unheard of multiple drives failing.

Yes I’m using some splitters but following max power limits of each line from the PSU.

Definitely under max power limits. But the splitter is used for length more than extra power.

I have 3 separate lines coming out and one of them has a splitter for power to extend it.

Also want to mention it’s been this way for 4 years working just fine. Not saying that nothing can go wrong.

I wouldn't have restarted the array if things weren't working well. Just seems coincidental the timing to a drive that was bad being replaced to potentially some cables being bad as well.

Just wondering if I should let the parity finish before installing new cables and such hoping some of the issues will go away. Like the one parity with errors. Its still plugged in and saying there's no errors using SMART

Any directions?

Edited April 13Apr 13 by Cor4eyh

48 minutes ago, Cor4eyh said:

Any directions?

Stop parity and sort out the drive issue

Errors on parity are not logged as a disk problem; check/replace its cables and post new diags after array start.

There is possibly a container constantly restarting and spamming the log, see if you can find out which by looking at their uptimes.

This is the current mission disk. It’s in unassigned devices. I cannot mount it. I am attempting xfs_repair to fix the file system. Anything else I can do?

The data that was on this disk in the array was being emulated. When the parity had errors it began to rebuild without disk 4 now there is no data on disk4 that data is sitting on the errored drive and unable to be rebuilt by parity since it doesn’t exist.

New diagnostics attached

tower-diagnostics-20260414-0041.zip

Diags are not after a reboot, did you replace the cables? Even if you don't, you will need to reboot first, then new diags after array start

6 hours ago, Cor4eyh said:

The data that was on this disk in the array was being emulated. When the parity had errors it began to rebuild without disk 4 now there is no data on disk4 that data is sitting on the errored drive and unable to be rebuilt by parity since it doesn’t exist.

Since you had dual parity, emulation of disk4 should have worked assuming no other problems. But what exactly do you mean "no data". Is it mountable but empty? That wouldn't be caused by emulation or rebuild.

2 hours ago, JorgeB said:

new diags after array start

Start in normal (not maintenance) mode.

5 hours ago, JorgeB said:

Diags are not after a reboot, did you replace the cables? Even if you don't, you will need to reboot first, then new diags after array start

They are after shut down and start up with drives back to normal. I’m in normal mode.

Disk 4 was nearly full. At least I think so. I can’t answer if it was. When I click on disk 4’s contents via Krusader it has 2 folders with nothing in them.

wierd that emulation would save 2 folders but not the other data correct?

I have disk 4 still attached but in unassigned devices because it has data on it.

I cannot mount disk 4 through maintenance the screen shot is of disk 4’s log. What should I do to mount that drive and hopefully save the data?

3 minutes ago, Cor4eyh said:

Disk 4 was nearly full. At least I think so. I can’t answer if it was. When I click on disk 4’s contents via Krusader it has 2 folders with nothing in them.

wierd that emulation would save 2 folders but not the other data correct?

My guess is that you formatted it then something created those folders after the format.

5 minutes ago, Cor4eyh said:

What should I do to mount that drive and hopefully save the data?

You can check filesystem with Unassigned Devices.

5 minutes ago, trurl said:

My guess is that you formatted it then something created those folders after the format.

You can check filesystem with Unassigned Devices.

I tried to run check filesystem with unassigned and got that photo back of the drive.

When starting the array it said a drive was unmount able format to continue. Since I have disk 4 and it’s still attached I clicked yes to format. Then saw it format disk 4.

Would maintance mode help with unassigned disk 4?

I tried to mount and get an error. If I could mount disk 4 I could put its contents back in the array.

2 minutes ago, Cor4eyh said:

When starting the array it said a drive was unmount able format to continue. Since I have disk 4 and it’s still attached I clicked yes to format. Then saw it format disk 4.

Format is a write operation. It writes an empty filesystem to the (in this case, emulated) disk. Unraid treats this write operation just as it does any other in the parity array, but updating parity. So parity agrees the emulated disk has an empty filesystem, and an empty filesystem will be the result of rebuilding.

The correct thing to do when you have an unmountable disk, whether disabled/emulated, or not, is check filesystem.

7 minutes ago, Cor4eyh said:

I tried to run check filesystem with unassigned and got that photo back of the drive.

The only thing I see in that is syslog where you attempted to mount the unmountable unassigned drive. Did you read the check filesystem link?

And please, screenshots, not photos.

Check filesystem on the unassigned disk and post a screenshot of the output from check filesystem.

32 minutes ago, Cor4eyh said:

They are after shut down and start up with drives back to normal.

Sorry, saw the date, and they were from yesterday for me, probably because of the time zone iffernce.

Emulated disk4 wasn't mounting; it needed a filesystem check, but looks like it was formatted now? Do you have the old disk intact?

11 minutes ago, JorgeB said:

Sorry, saw the date, and they were from yesterday for me, probably because of the time zone iffernce.

Emulated disk4 wasn't mounting; it needed a filesystem check, but looks like it was formatted now? Do you have the old disk intact?

I do have the old disk it’s intact and attached as an unassigned device that’s unmountable.

Currently parity is rebuilding parity due to the parity disk error.

Should I stop parity. I will only have 1 parity drive at the moment.

And try maintenance mode to repair the unassigned disk 4 file system?

While I was worried about the format I have disk 4 attached it’s just needing a file system repair. I attempted fixed without going into maintenance mode with no success yet.

I know I made mistakes here and I’ll accept my own faults for that. In the future things will go differently.

I still have the drive it appears to still power on and show it’s connected just unable to mount it in unassigned

46 minutes ago, trurl said:

Check filesystem on the unassigned disk and post a screenshot of the output from check filesystem.

I assume thats by clicking the check filesystem button next to the unassigned drive correct?

How long does that take?

It's going currently waiting for a finish to post the results.

6 minutes ago, Cor4eyh said:

How long does that take?

Depends, maybe not long unless it has to search for secondary superblock.

It's been going for a few minutes I will let it run.

This is what I'm seeing so far.

It should show a FIX option when that scan is done; click it.