Put in new drives in my Synology NAS DS920+ and it says that there are 3 damaged sektors in one of them. What to do?

[Jonamatata]

I have a synology NAS DS920+ with 2 8TB Drives and i expanded it with 2 16 TB drives and it has been installing/expanding for a day or 2 now and it says that there are 3 damaged sektors on drive 3. Should i contact the retailer to get it replaced or ist it fine? Can i repair the damaged sektors? Was it something i did during the handling of it?
What do i do?

 

[EAZ1964]

A few bad sectors is not very serious, just something to watch carefully. The system will repair/ exclude the sectors.
Best to have the raid rebuild completely and see if it stays at 3. If more bad sectors develop in coming days/ weeks/ months it is time to return them.

 

[Jonamatata]

A few bad sectors is not very serious, just something to watch carefully. The system will repair/ exclude the sectors.
Best to have the raid rebuild completely and see if it stays at 3. If more bad sectors develop in coming days/ weeks/ months it is time to return them.

Thanks, i just wonder how i rebuild raid completely?

 

[jeyare]

it is not so easy as was explained

OP doesn’t mentioned file system used:
- when ext4, you can easy rebuild you superblock. Problem is when some inodes are corrupted, even directory entries. Synology DSM can’t handle it by itself. Reallocating of data from the blocks can be contra productive by FS, when their content is actually overwritten by OS. Better is use method - unmount the drives from the NAS and run it externally with fsck.ext4 or from Win with HDsentinel to check it in better way

- when btrfs it is even worse. because btrfs doesn’t track bad blocks. Additionally, scrub could be taught to test for bad blocks when a checksum error is found. This would make scrub much more useful; checksum errors are generally caused by the disk, but while scrub detects afflicted files, which in a backup scenario gives the opportunity to recreate them, the next file to reuse the bad blocks will just start getting errors instead.

From all the aspect. Damaged block and new HDD is not good start and you need to check them out if the NAS.

just to be sure

 

[Jonamatata]

it is not so easy as was explained

OP doesn’t mentioned file system used:
- when ext4, you can easy rebuild you superblock. Problem is when some inodes are corrupted, even directory entries. Synology DSM can’t handle it by itself. Reallocating of data from the blocks can be contra productive by FS, when their content is actually overwritten by OS. Better is use method - unmount the drives from the NAS and run it externally with fsck.ext4 or from Win with HDsentinel to check it in better way

- when btrfs it is even worse. because btrfs doesn’t track bad blocks. Additionally, scrub could be taught to test for bad blocks when a checksum error is found. This would make scrub much more useful; checksum errors are generally caused by the disk, but while scrub detects afflicted files, which in a backup scenario gives the opportunity to recreate them, the next file to reuse the bad blocks will just start getting errors instead.

From all the aspect. Damaged block and new HDD is not good start and you need to check them out if the NAS.

just to be sure

I am fairly new at this so i didn't entirey understand what to do from your description, sorry.
But first things first: How do i see what file system i have?

Edit: I just found it, i have btrfs, what do i do now? And should i wait until it has expanded completely?

 

[jeyare]

when you have such elementary question do nothing because the damage will be even worse.
It is not simple as “click to this icon”.

You can read more here:

Identify damaged files - ArchWiki

wiki.archlinux.org

 

[EAZ1964]

I see there are some slightly different opinions here.
my view is: complete the installation of the disk(s), as pulling them in the middle of the expansion process may not work out (Should do, but never sure).
the errors were detected during the parity build so no data is lost. the blocks should be marked on the disk.
Then, run the full smart and see what the disk status is regarding bad blocks and status.
if it is just a few, and no more developed in meantime, I would be ok with the disk. I more develop over time, it is time for a RMA.
If I understand well, Jeyare suggests to take the disk out and check it in a W10 PC with a tool like seatools. A good option.

 

[Telos]

I see there are some slightly different opinions here.

That's why we call this a "forum"

So here's another POV... Let things finish. After that, shut down and test the drive using the OEM diagnostic software run from a PC.

With bad sectors, you likely have an opportunity to an RMA exchange. You can either give that a go, or continue to operate, keeping an eye on increased bad sector counts. If bad sectors remain at a relatively low level (ex. 2-3), I would not bother with an RMA. If the count rises to 15+ over the next 12 months, I'd certainly be applying for an RMA before warranty expires.

RMA exchange can be a hassle... If you go this route, I recommend you request the provider to send the replacement before you return the faulty unit. This may require a credit card hold, or even payment, until your faulty drive is received. With the replacement in hand, you'll need to “repair” the array, unless you have an empty slot and use DM7's drive replacement feature. Once everything is up and running, you should wipe the faulty drive (use a PC… if Windows, see “diskpart clean all”), before returning it.