Failing Drive - Remove before replacing

[AzureMurph]

Hi All

Sorry to start another thread but I have more than one question so hope you don't mind me starting a new one.

Setup is a DS412+
Firmware version DSM 6.2.4-25556

Drive config is Raid5 with data protection
4 drives installed all identical.

Due to some unexpected power outages which have caused ungraceful shutdowns.
Drive 3 is reporting multiple bad sectors, I/O errors.
It's on it's last legs.

First question, instead of replacing it straight away, can I amend the config and just remove it?
I know this will lead to less redundancy, fault tolerence etc.
But I want to remove it to start with.
Can someone advise on how I go about reconfiguring the NAS so I can safely remove the failing drive.

Once I've done that.

If I want to replace the removed drive.
What are the advisable best practices?
If I can't get hold of a like for like drive, what would be the consequences of buying a different drive with different capacity/speed/specs etc?

Trying to work out what is the best approach. I don't want to end up replacing all four drives if I can help it.

Many Thanks

-- post merged: 10. May 2021 --

-- post merged: 10. May 2021 --

 

[EAZ1964]

It is not possible to downgrade a 4 disk raid5 to a 3 bay non raid.
This requires full formatting and reinstall. Also, that means that if one disk fails, you lose all data.

You can replace the failing disk with any other disk, as long as it is same size or bigger, but do not use a SMR disk!
All described in the fine manual of synology.

 

[AzureMurph]

Hi Eaz,

Thank you for that. It's what I thought, hence wanted to check with yourselves.
Considering clearing up all the data (remove anything that I no longer need).
Then migrate all the data across to another storage device in the interim.
Then start again with the NAS, wipe all config, replace some drives if needed.
Basically start afresh with it.
Then migrate all the data back to it.

Cheers for the response. Appreciated.

 

[fredbert]

If you haven't already, you should look to use a UPS so that the NAS doesn't get shutdown from power outages.

 

[AzureMurph]

Hey Fredbert

Totally agree and sound advice.

It's a long story, as to why I am having power issues.
Currently not living at my house, which has meant I've had to setup all my kit as best I a can.
Sodding toaster has been taking out the electrics.
Again, long story. But yes, UPS is a great idea. One thing at a time for me at the moment though.

Cheers

 

[AzureMurph]

As a follow up.

I migrated all the data off the NAS.
Swapped the failing drive out.
Rebuilt it as RAID 6.
Three of the drives are the originals, so they will more than likely fail sooner rather than later.
Hence raid 6, gives me wiggle room with two failed drives allowance.

Went with a UPS as well. Something I neglected to implement first time round.