QNAP mirrored drive failed

Yep, should work. The new disk must have at least the capacity of the old one, but otherwise a straight swap should be fine. After you install it, the light will flash red and green for a while, and Raid will rebuild itself. The light goes green again at the end.  You can monitor it on the dashboard.

Of course, the bigger question is: why bother with Raid? I get that you've been able to listen to music on the QNAP in the meantime, but it seems like a small benefit for all the hassle, noise and cost. Just my two cents.

Thanks. Why bother with Raid? - good question. I suppose it is just another layer of defence and keeps the music going without having to resort to copying from the back up which would take 20* hours.

Another question - do I in fact need to turn off the NAS whilst doing the physical swap?

According to QNAP's website the TS-412 supports hot swapping so you should be safe to remove and replace the disk while the NAS is running. 

As you have discovered, whilst RAID is not a backup it does allow you to continue enjoying the music in the event of a drive failure. 

Richard 

trickydickie posted:

According to QNAP's website the TS-412 supports hot swapping so you should be safe to remove and replace the disk while the NAS is running. 

As you have discovered, whilst RAID is not a backup it does allow you to continue enjoying the music in the event of a drive failure. 

Richard 

Not only does RAID allow you to continue to enjoy the music in the event of a disk failure, it allows you to  continue to actually have the music in the event of a drive failure.

Here speaks one who, with 40 years in IT, has dealt with more than his fair share of drive failures 

...and since an HDD is an electro-mechanical thing, every HDD will fail at some point   (the jury is still out on those SSD drives though... introduced just after I retired from active employment). 

I am in IT as well, agree with everything you say. 

With regards to SSD's we have had more of these fail than traditional hard drives. Trouble with them is that when they fail they do so catastrophically. 

We may have been unlucky, since changing make to Kingston we have had no issues and they do give a tremendous performance increase 

For what its worth I had a similar problem with my QNAP 412 over last Christmas / New Year.  I hot swapped a larger drive for the faulty one - I had no problems as it rebuilt itself (Ian from UHES was in Cuba with Norman at the time ... so no help there ...).

My only complaint was the system had not sent an email to either Ian or me telling me the drive was faulty ...

trickydickie posted:

I am in IT as well, agree with everything you say. 

With regards to SSD's we have had more of these fail than traditional hard drives. Trouble with them is that when they fail they do so catastrophically. 

We may have been unlucky, since changing make to Kingston we have had no issues and they do give a tremendous performance increase 

The potential reliability of SLC SSD exceeded the best HDDs about 3 or 4 years ago, but, by then, most manufacturers had already switched to MLCs for general SSDs production.  Since then, the only SLC SSDs either were/are old designs (unreliable) or specifically designed for high reliability (and very expensive!).

From some manufacturers, MLC SSDs started to have an overall reliability advantage about 2 years ago.  Most of the current generation SSDs from most manufacturers now have a reliability advantage (but there are still exceptions).  Don't forget that HDD reliability is also variable and usage dependant.

As advised above, you can hot swap the disk without powering down.

On the subject of anecdotal observations of higher SSD failure rates - same here. The big picture might be different but the parochial picture is clear. SSDs are not as reliable as conventional platters and are not favoured here or recommended to my clients. Still not a cheap option either.

I had the same problem last week with my Netgear ReadyNAS Ultra 4. I've replaced the dead drive with a brand new one but it's failed to resync, and am now being told that the other drive may be close to failing too. Am getting prompt responses from the Netgear forum which I'm working through to try and resolve.

Just to update - I received my new drive and hot swapped it for the defective mirrored drive over the weekend. This was easy to do and within a minute or so of inserting the drive it started rebuilding which took around 6 hours. All is ok now which is a relief.