Raid 5 inaccessible after defective drive swap

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Richard
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Re: Raid 5 inaccessible after defective drive swap

Post by Richard »

Mounting an external harddisk via usb... that might be a possibility indeed. Good tip, thank you!

As I'm not native English, you might have misunderstood me. I know raid on itself is not a backup system but redundancy. But that is why I didn't expect it would go wrong with only 1 disk having a failure.
I use the NAS (with the raid) as my personal backup system, for my bookkeeping, documents and images, so as said I still have the originals also and am able to create a new backup as long as my pc does not crash now at this moment. :)
So don't worry, I don't use raid as backup system, I use the NAS as personal backup. Only the movies and music is not as backup on the NAS because that is pity, but not critical.

Anyway, thank you for helping me out and your quick answers, that is very appreciated, thank you very much!!
I also hope it will be fixed and ofcourse if it will be, I will mention it in this thread for future references.
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Nazar78
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Re: Raid 5 inaccessible after defective drive swap

Post by Nazar78 »

Richard wrote:Mounting an external harddisk via usb... that might be a possibility indeed. Good tip, thank you!

As I'm not native English, you might have misunderstood me. I know raid on itself is not a backup system but redundancy. But that is why I didn't expect it would go wrong with only 1 disk having a failure.
I use the NAS (with the raid) as my personal backup system, for my bookkeeping, documents and images, so as said I still have the originals also and am able to create a new backup as long as my pc does not crash now at this moment. :)
So don't worry, I don't use raid as backup system, I use the NAS as personal backup. Only the movies and music is not as backup on the NAS because that is pity, but not critical.

Anyway, thank you for helping me out and your quick answers, that is very appreciated, thank you very much!!
I also hope it will be fixed and ofcourse if it will be, I will mention it in this thread for future references.
That is a relief :D I was afraid of the otherwise. Same here I also have tons of junks in the nas most of them like movies, music, softwares you get what I mean. But the valuable data like vids, photos, docs, settings from user mounts etc I have two separate nightly backups, one copied from nas raid10 to the usb raid5 and the other rsync to off-site. No problem do let us know the end results.
AS5304T - 16GB DDR4 - ADM-OS modded on 2GB RAM
Internal:
- 4x10TB Toshiba RAID10 Ext4-Journal=Off
External 5 Bay USB3:
- 4x2TB Seagate modded RAID0 Btrfs-Compression
- 480GB Intel SSD for modded dm-cache (initramfs auto update patch) and Apps

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Richard
Posts: 66
Joined: Sat Jan 03, 2015 4:38 am

Re: Raid 5 inaccessible after defective drive swap

Post by Richard »

Wow NAS raid 10 cool.
Indeed for my little company I also have 2 backups. Loose documents on a NAS with 2 disks in raid 1 and image files of the complete disks on the Asustor in raid 5. And present on my pc ofcourse.
Redundant backup is just a must for really important things. Normally not 2 things go bad at the same time... but there are those days that Kilroy was here... or ... there is a saying (kindlike Kilroy but something else) in English which I like, but I got a memory leak at the moment, and don't recall it, LoL. :)
Anyway, with very important things, always expect the unexpected.
Richard
Posts: 66
Joined: Sat Jan 03, 2015 4:38 am

Re: Raid 5 inaccessible after defective drive swap

Post by Richard »

Hello @Nazar78.

This morning I had a reply from Asustor, asking to swap disk, which I already did several times. I hope they will look to the thread this time.

However, just to be sure I wanted to try and backup some movies to an external hard disk. Firstly I tried to find the content on my NAS.
But I couldn't find anything.

In which directory do I have to look to find my user files which were on the NAS?
There are so many directory's and I don't know where to look as I don't see a /home directory that quickly and I don't have a clue where my files would reside.
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Nazar78
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Re: Raid 5 inaccessible after defective drive swap

Post by Nazar78 »

Hi Richard,

/home is a symlink to /volume1/home.

So your data from the raid5 /dev/md1 is mounted on /volume1.

But I'm afraid since your raid5 failed to mount, this path will not be available or empty.

I think the final attempt is to assemble your raid5 in usb enclosure (or if you have 4 spare sata slots) on ubuntu/debian desktop box with mdadm installed. Some reference here https://support.asustor.com/index.php?/ ... using-a-pc.
AS5304T - 16GB DDR4 - ADM-OS modded on 2GB RAM
Internal:
- 4x10TB Toshiba RAID10 Ext4-Journal=Off
External 5 Bay USB3:
- 4x2TB Seagate modded RAID0 Btrfs-Compression
- 480GB Intel SSD for modded dm-cache (initramfs auto update patch) and Apps

When posting, consider checking the box "Notify me when a reply is posted" to get faster response
Richard
Posts: 66
Joined: Sat Jan 03, 2015 4:38 am

Re: Raid 5 inaccessible after defective drive swap

Post by Richard »

Oke thank you very much.

At this moment Asustor has already replied and ackknowledged the issue.
They will try to rebuild the raid themselves, which is a very great service imho.
I will let you know the outcome of this.
Richard
Posts: 66
Joined: Sat Jan 03, 2015 4:38 am

Re: Raid 5 inaccessible after defective drive swap

Post by Richard »

I promised to mention the outcome, which is not good.

According to support, the old disk 4 does not contain any partitions.
They can't rebuild the raid, because one disk, responsible for /dev/sdb4 is stuck in a rebuilding process. I can't see that with the cat /proc/mdstat command but I assume they are right.
Since that makes 2 unavailablel disks, the raid can't be repaired and data is lost.
We assume that rebuilding was the time when you put back your disc the first time. The hot swapping afterwards may have interrupted the rebuilding and made sdb4 faulty.
That is indeed what I said I did on the previous page. So my action here maybe have triggered this.

But it seems I lost al the data and have to create the raid newly.

I checked the link you gave me, but there is spoken of /dev/md1 which does not exist anymore in my case. So I'm afraid I lost al data on the disks.

Still very odd that I tried to do it as decent as possible (in the old days pc always were tearned off when replacing disks) and raid did not rebuild. Also a previous time I had to restart the system twice before the rebuild begain. So I'm wondering if more people with a 304T had raid rebuilding issues.

Anyway, thank you for all your help.
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Nazar78
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Re: Raid 5 inaccessible after defective drive swap

Post by Nazar78 »

Sorry for the lost. Maybe now that the raid5 is newly created with no data this might be a good time for you to test around i.e. remove the disk reboot vs remove the disk then hot-swap. It might save you the trouble in the future.
AS5304T - 16GB DDR4 - ADM-OS modded on 2GB RAM
Internal:
- 4x10TB Toshiba RAID10 Ext4-Journal=Off
External 5 Bay USB3:
- 4x2TB Seagate modded RAID0 Btrfs-Compression
- 480GB Intel SSD for modded dm-cache (initramfs auto update patch) and Apps

When posting, consider checking the box "Notify me when a reply is posted" to get faster response
Richard
Posts: 66
Joined: Sat Jan 03, 2015 4:38 am

Re: Raid 5 inaccessible after defective drive swap

Post by Richard »

Sorry for the lost.
Thank you. Luckily it was no real important data. The movie files can be restored but need to be converted or downloaded again, so only a lot of work.
The important things are still originally present and on another backup system, so no worries there. :)

Indeed a good time to test raid rebuilding when a new volume is created. I will surely do that as I have plans to increase the size to 4x4TB. Which I also could do now, but I rather know for certain that the system works correctly. But I will probably do this upgrade also with still empty disks. ;)
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