I had a catastrophic failure of my 4 drives on my RN104 earlier this year (all the same WD Red, but bought at different times). I recall last time simply plugging the new drives in and seeing the total capacity increase, which seemed fine. However, all four failed within a couple of days (starting while I was on holiday, so unable to physically get to them).
I've since been running it with a single 14Tb drive, and have now bought another.
I confess I don't understand RAID at all. What I would like to achieve is to not have the concern of a single drive's failure losing any data. Could anyone point me in the right direction as to how to install the second drive to ensure data integrity. I'm happy to purchase further drives if required.
What I would like to achieve is to not have the concern of a single drive's failure losing any data.
XRAID by default uses a combination of RAID-1 and RAID-5. Neither will lose data if a single drive fails.
The main vulnerabilities that result in data loss are
A second drive failure is uncovered while a replacement drive is being resynced (reconstructed).
A power failure or other crash results in cached writes being lost - resulting in an array which is out of sync.
Part of my own mitigation here is to periodically run the disk test and scrub options maintenance tasks. I rotate through all 4 maintenance functions 3x a year (running one per month). Disk test and scrub are two months apart. The idea here is to uncover disk issues early.
Another component is to protect the NAS from power failures with a UPS. If you don't have one, then I definitely recommend getting that.
The final component is to have a solid backup plan for the NAS.
Could anyone point me in the right direction as to how to install the second drive to ensure data integrity. I'm happy to purchase further drives if required.
I'd test it first in a PC with vendor tools (Seagate's Seatools or WD's dashboard). A full non-destructive test will take about a day. Generally I follow that up with an erase disk test (which takes another day). Seatools and WD's older lifeguard software have that test, but WD's dashboard does not.
Once it passes those tests, I'd hot insert it into the NAS. That should automatically create RAID-1 (mirrored drives). If a single disk fails, you can boot up with just the second.
