Dear community,
I’m running my Qnap TS-231P for almost 8 years now without any problem. As I host there quite sensitive data (photos etc.. :-)) I think it would be a good idea to replace the HDDs before one of they fail.
I have 2x 2 TB WD20EFRX as a RAID1 installed.
How I’m going to replace the HDD one by one with fresh ones, without losing data? I also intend to keep the old ones as a further backup. Does this makes sense?
Thanks a lot for your help!
First question, do you have a backup? (ALWAYS have a backup..RAID is NOT a backup!)
For the question, you can either replace the drives with same or larger size to expand, both is explained in the manual
Only if you ALREADY have a backup in place and verified. Never make any changes without first having a backup. You indicate the data is important to you. Never count on reinserting old drives into the NAS to recover data as your only backup.
Or your NAS bit the bullet and you now try to get the data off these drives (you cannot insert them into windows/mac/Linux and plainly read them without knowhow or special software)
Many thanks for your reply. Yes, I do have a backup on an external drive and on a cloud storage. However, I don’t want to risk to destroy the RAID, but just replace one by one and make the QNAP doing the job.
I bought the very same HDDs again. What I found in the direction for use is the following:
Go to Storage & Snapshots > Storage > Disks/VJBOD
Disks, select a disk, and click Action >
Replace.
This replaces the disk with a spare disk. After all data
on the selected disk has been copied to the spare disk,
the selected disk will be safely removed from the RAID group and the system.
So does that mean that the HDD left then holds all data and can copy them to the new disc? And as soon this is done I do the very same with the other HDD?
Thanks and sorry for the maybe silly questions.
just hotswap the disk..no need to mark any disks for any action..easy
thanks. Swapped the first one. All seems ok. Thanks a lot for your help!
But I think you will want to WAIT for the RAID to rebuild between each HDD swap.
We highly appreciate your proactive approach to disk replacement; it is indeed an effective way to significantly minimize the risk of data loss.
In addition, we strongly recommend maintaining an off-site backup for your critical data to safeguard against unforeseen incidents. Please feel free to reach out if you encounter any issues during the process.
Thank you for your feedback!
Dear All, with your help I successfully introduced new HDDs into my NAS. System is healthy and all data seem available. Before the disk swap I generated a fresh offline backup. Moreover I have a cloud backup of the most important data (pictures etc…). After replacement of the first disc, I double confirmed that the mirroring process is finished and was successful.
I only noticed, that the HDDs I recently bought seems to have an older firmware than those ones I bought almost 8 years ago. I haven’t found any way to update the firmware and maybe this is also not needed. I just found it strange. But this is clearly no QNAP topic 
Again, thanks a lot and have a nice day!