RAID1 to single disk

Questions about SNMP, Power, System, Logs, disk, & RAID.
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Re: RAID1 to single disk

Post by SantaFox » Mon Nov 21, 2022 5:11 pm

Hi all,

I've followed this procedure for my TS-451DeU and two M2 SSDs in RAID1 used for system disk (it's too much and I want one for SSD cache). However in the end of procedure RAID1 works well with first SSD, but second SSD is marked as Faulty, and thus not available for system. Have tried to clear the superblock, but no result.

What I can do, preferrably without removing this M2 SSD?
NAS error.png
P.S. I think it is possible with creation of another one one-disk RAID1 on this faulty disk and later destroying it, but I am not sure that it is good idea. A command that I plan to this:

Code: Select all

mdadm --create --assume-clean --level=1 --force --raid-devices=1 /dev/mdX /dev/sdXY
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Re: RAID1 to single disk

Post by SantaFox » Tue Nov 22, 2022 1:36 am

P.S. Found a working solution here:

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Re: RAID1 to single disk

Post by docentt » Wed Nov 23, 2022 9:00 pm

mva68 wrote:
Thu Apr 14, 2022 6:05 pm
ganekogorta wrote:
Sun Sep 15, 2019 7:05 am
MrVideo wrote:Nope, no can do. Why would you want to? If your single HDD fails, you've lost it all.
If I want to change/upgrade one disk that contains system to a bigger disk.

For example: initial TS219 with one 2TB disk and final TS219 with one 6TB disk.
Mi idea is introduce the 6TB, build a raid1, extract the 2TB disk, “downgrade” the raid1 to single disk and expand the volume from 2 to 6 TB

Un saludo
Agur eta ondo ibili
Thanks a lot for the detailed procedure.
I want to move a non-system Storage Pool on 2x Raid1 5Tb disk to 1x Single 16 Tb disk. NAS: HS-453DX.
The system is on Raid1 M2 SSD's so won't be bothered.
I understand the procedure to move RAID1 to a Single disk with the same Storage Pool on the 1x 16Tb disk.

But I assume then the Storage Pool size will still be 4.54 Tb, how to expand to 14.55 Tb available on 16Tb disk. Or is this done automatically?
I have followed the procedure and managed to swap to a larger drive, but the Storage Pool size is the same as it was before the disk swap (ganekogorta thank you for the detailed description!).

I have the same question as mva68: How to expand the Storage Pool size?
QNAP NAS did not do it automatically and there is no option in GUI to do the extension, you can just extend by adding a RAID group, so maybe the question should be:
How to extend the RAID group capacity for a single drive with CLI or GUI?

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Re: RAID1 to single disk

Post by P3R » Thu Nov 24, 2022 6:38 pm

docentt wrote:
Wed Nov 23, 2022 9:00 pm
QNAP NAS did not do it automatically and there is no option in GUI to do the extension...
The way to expand a pool in the GUI when disks have increased in size is by using the Replace Disk One by One feature.

If that feature is unavailable then there is no way to do it in the GUI. It's logical if that feature is greyed out for you as there is no way to use it with a non-redundant RAID groups and there is no supported way to end up in your situation with a single disk. If this is the case then CLI is your only option.
RAID have never ever been a replacement for backups. Without backups on a different system (preferably placed at another site), you will eventually lose data!

A non-RAID configuration (including RAID 0, which isn't really RAID) with a backup on a separate media protects your data far better than any RAID-volume without backup.

All data storage consists of both the primary storage and the backups. It's your money and your data, spend the storage budget wisely or pay with your data!

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