RAID 5 "Add a new disk" not working

[SJLPHI]

Hello,
I had a pretty bad day trying to upgrade my aged HDDs on my Qnap 419+. One of the new HDD died during rebuilding my RAID 5 and I had to reboot the NAS during RAID 5 rebuild, here's what happened:
Disk 1 dies while rebuilding RAID 5 after replacing Disk 3.
For some reason port for Disk 1 just didn't respond and I had to reboot to access the NAS.

Disk 1 replaced with an old drive that originally stored data from RAID 5, no data seems lost!
Disk 3 is set to "single volume" and I cannot seem to be able to delete the volume. Using the volume manager GUI I try to use the "add drive" to the RAID 5, it actually does nothing and sends me back to configuration. I tried this many times and tried rebooting the NAS a cew times too with nothing working.

Right now, I am stuck with RAID 5 of disk 1, 2, 4 in degraded mode and disk 3 stuck in 'single volume'.

I am lost. what am I supposed to do?

Right now I am planning to try destroying the partition table using fdisk on disk 3, then hot-replugging and hoping for the best, anything else?

[SJLPHI]

and.. that didn't work.

I am so frustrated, any suggestions?

[SJLPHI]

[SJLPHI]

[SJLPHI]

Well spamming the same "add new disk" eventually worked....





Now the question... Why and how to make sure that it goes smoother next time?

[SJLPHI]

and that failed after 5 mins and now I'm stuck with a system that says "RAID 5 volume not defined". and I can't do anything...

[dolbyman]

Just kill the RAID and start from scratch, restore from backups

[SJLPHI]

I am backing up... you know 3 TBs at 30MB/s takes days! Unless if you have a suggestion on speeding this up.

[OneCD]

I am backing up... you know 3 TBs at 30MB/s takes days! Unless if you have a suggestion on speeding this up.

Where is your backup HDD attached? Directly to the NAS? Or to your PC?

Are you using a cloud backup service?

[dolbyman]

my 419p+ does 50-70MB/s to SMB targets

[SJLPHI]

backup HDD is attached to a laptop that is connected through the router via ethernet connection.

[OneCD]

backup HDD is attached to a laptop that is connected through the router via ethernet connection.

Connecting the backup drive directly to the NAS - then getting the NAS to copy your files across - is usually quicker than going the long-way through your laptop. And it means you won’t need to keep your laptop powered-up.

Your current config can introduce a couple of potential bottlenecks that may slow your transfer down.

Edit: just noticed your NAS only has USB2.0 ports. Technically, 1Gb/s Ethernet beats that, so I guess you’re already using the fastest method.

[SJLPHI]

So the backup has been completed and now I tried to delete the RAID 5 volume... that doesn't do anything! WTF! Do I have to factory reset the NAS for this?

[SJLPHI]

Well I got ticked off and started re-initializing.

[SJLPHI]

Well what do you know... another drive died during the re-initialization. It seems that all HDDs that gets connected to Bay 1 goes bust... I am going to stick in a spare HDD on Monday and hopefull that's the last time I have to touch it.