How to replace a failed or faulty HARD DISK on your QNAP NAS

It's not something we hope for, but unfortunately from time-to-time hard drives fail. In this video, we show you how to replace a failed hard disk in your QNAP NAS.

We recommend that as well as backing up your data on a regular basis, make sure you always configure your drives with some level of RAID (Redundant Array of Inexpensive Disks).

What Are the Types of RAID?

RAID 0 (Striping) (Not recommended)

RAID 0 is taking any number of disks and merging them into one large volume. This will greatly increase speeds, as you're reading and writing from multiple disks at a time. An individual file can then use the speed and capacity of all the drives of the array. The downside to RAID 0 though is that it is NOT redundant. The loss of any individual disk will cause complete data loss. This RAID type is very much less reliable than having a single disk.

RAID 1 (Mirroring)

While RAID 1 is capable of a much more complicated configuration, almost every use case of RAID 1 is where you have a pair of identical disks identically mirror/copy the data equally across the drives in the array. The point of RAID 1 is primarily for redundancy. If you completely lose a drive, you can still stay up and running off the additional drive.

In the event that either drive fails, you can then replace the broken drive with little to no downtime. RAID 1 also gives you the additional benefit of increased read performance, as data can be read off any of the drives in the array. The downsides are that you will have slightly higher write latency. Since the data needs to be written to both drives in the array, you'll only have the available capacity of a single drive while needing two drives.

RAID 5/6 (Striping + Distributed Parity)

RAID 5 requires the use of at least 3 drives (RAID 6 requires at least 4 drives). It takes the idea of RAID 0 and stripes data across multiple drives to increase performance. But, it also adds the aspect of redundancy by distributing parity information across the disks. There are many technical resources out there on the Internet that can get down into the details as to how this actually happens. But in short, with RAID 5 you can lose one disk, and with RAID 6 you can lose two disks, and still maintain your operations and data.

RAID 5 and 6 will get you significantly improved read performance. But write performance is largely dependent on the RAID controller used. For RAID 5 or 6, you will most certainly need a dedicated hardware controller. This is due to the need to calculate the parity data and write it across all the disks. RAID 5 and RAID 6 are often good options for standard web servers, file servers, and other general-purpose systems where most of the transactions are reads, and get you a good value for your money. This is because you only need to purchase one additional drive for RAID 5 (or two additional drives for RAID 6) to add speed and redundancy.

RAID 5 or RAID 6 is not the best choice for a heavy write environment, such as a database server, as it will likely hurt your overall performance.

It is worth mentioning that in a RAID 5 or RAID 6 situation if you lose a drive, you're going to be seriously sacrificing performance to keep your environment operational. Once you replace the failed drive, data will need to be rebuilt out of the parity information. This will take a significant amount of the total performance of the array. These rebuild times continue to grow more and more each year, as drives get larger and larger.

RAID 10 (Mirroring + Striping)

RAID 10 requires at least 4 drives and is a combination of RAID 1 (mirroring) and RAID 0 (striping). This will get you both increased speed and redundancy. This is often the recommended RAID level if you're looking for speed, but still need redundancy. In a four-drive configuration, two mirrored drives hold half of the striped data, and another two mirror the other half of the data. This means you can lose any single drive, and then possibly even a 2nd drive, without losing any data. Just like RAID 1, you'll only have the capacity of half the drives, but you will see improved read and write performance. You will also have the fast rebuild time of RAID 1.

Where to buy your QNAP NAS

[NoMusiciansInMusicAnymore]

I just swapped out a drive while watching your video, thank you so much, that was so much simpler than expected! so simple I would have been extremely nervous without your company haha

[sgb]

Clear video, direct and without unnecessary fuss. I like it. Keep it up!

[BlindFury]

Oh wow this is so staight forward and simple.
Thank you for your video I wish I could like it twice.

[steveharvey]

Hi, Thanks for the video, I have a similar problem as have many people online. I have an 8 bay QNAP NAS (TS-879 Pro) populated with 6Tb WD Red drives, running raid 5. a short time ago I had a S.M.A.R.T. error saying normalised attributes were below manufacturers specs. two days later drive 5 popped up with the same error, I purchased two new identical drives, started to hot swap drive 2, got a database self recovery started message, all was well with the unit for about 3 hours, thereafter both degraded drives came up with a red error and QNAP went into read only mode. I left it over night and this morning there is a message saying database self recovery completed but the red error is still there! The difference is that the replaced drive now says Disk Access Error (i/o) ERROR and disk S.M.A.R.T. information good! Disk 5 also says Disk Access History (i/o) ERROR but Disk S.M.A.R.T. still says WARNING1 Phew! what a long story, Could the Disk Access (I/O) error be because QNAP has placed its self in read only mode? Im at a a loss on what to do next, can you please point me in a direction? Sorry one more thing, I can see and retrieve all of my data using WinSCP.

[Aljallaf]

Thank you very much ... Worked prefect as you explained👌.

[nicg]

great tutorial, exactly the problem I'm facing and has shown clearly exactly what to
However my NAS won't automatically start rebuilding the storage pool and when I try to tell it to do it manually it simply says that it's possible that the rebuild is failing because a disk has been FML.

[paulsilaghi]

Hi there! I watched your video, great! I have question: disk 1 of my NAS (TS 231P2) show signs of failure; RAID is 1, disk 2 is in good shape. It is ok just to pull it out and replaced as you showed in the video with a similar one?

[calebthedark]

Nice and clear, what considerations should I have when it's about an SSD (part of a RAID 1 raid group) near end of estimated life, with cache type read-write and cache mode All I/O?

[Kielyism]

if you did this to increase the capacity of the nas, as in swap in a higher capacity drive. I suppose my question is I am coming to close to capacity on my drive 75%, so I was thinking of swapping the drives to increase cpacity etc.

[themoebius]

Is swapping the drive something that's *better* to do live while the device is on as shown, or while it is turned off? I would have assumed "off" until I watched this.

[londontrada]

I need to replace a disc, RAID group is currently synchronising, should I wait until it finishes?

[mrbuckwheet]

what about replacing a failed m.2 drive in raid 1?

[marc]

Hello,
I have following problem with my qnap ts-253 Pro, This after placing a larger Hdd and reinstallation, In local network I can open or copy files to my PC so this works normally. As for my samsung tablet i can open mp3 and mp4 and in contrast i can't open or copy any pdf or jpg files. An error message is given: "Failed to download"
I have tried everything, user access rights settings are set.
What could be the problem here.

The nas has 2 bays on installing i had problems with the 2é bay.
So I Now there is only a hdd in Bay 1 (I don’t think this can cause the problem I have)

Thanks, Marc.

[sci-fiintheverse]

If you're using Raid 0 what would be the procedure? The drive still works, could I do a temporary offload of just that drives data with the replacement as soon as it finished?

[hidemichiXT]

I am having the very same situation: one of the disks reports SMART issues. I am having another one empty for replacement in and my QNAP has one additional free bay. In the solution you shown there is a risk that if during the RAID rebuild one of other disks that contains the data fails we will be loosing entire array. Is there a possibility to place a good disk in a spare bay and 'do something' to ask QNAP to replace data from failed disk to new one and only after synchronization is done remove the one that has a SMART issues? Thanks

[andreiionescu]

How would one go about erasing the information on the faulty hard disk, before removing it?
I have a drive with similar SMART warnings and want to send it back for warranty, but wouldn't want to send the disk back with all my data in it.

[Fresh]

I have the same situation as in this video (RAID 5 disk failing). BUT I need to RMA the disk that is dying before I can swap it out ... what do I do in this situation? Is it as simple as remove the disk, shut down the NAS, wait for the replacement disk to turn up, turn NAS back on, insert new drive? Or something trickier...?

[edmundzed]

OK I replace my drive, so far so good nut now the new replaced drive is shown as "spare" why and how do I fix this?

[DanBurgaud]

I have a TS-431P with 4 drives (varying age), in RAID5.
Disk4 (oldest) has been showing bad sector errors lately, so I want to replace it.

5:30 If I dont go to UI, how do I know when to plug in the new drive?

[grahamcollingridge]

Do the replacement drives need to be the same size? Or can you replace a faulty drive with a larger capacity drive?