Have just added 2 x 3TB WD Red drives to my 314 by removing 2 of the 2TB Reds from the 4 off 2TB Reds installed. Currently rebuilding is going well. My question is, what is the best Raid configuration to have to give maximum storage capacity balanced against protection of data in case of a drive failure? Thank you in advance ps just upgraded to the 314 from a Duo v2
Your best protection against data loss would be a good backup strategy. Raid protects you against hard drive failure and keeps your data available if this happens. With the 314 you're probably best using Xraid, with 4 disks this will be raid 5.
What are you using at present?
I assume you either replaced 1 drive at a time or you had no data on the 314.
Thank you for the swift reply, yes I'm with Raid 5 at the moment, rebuild has finished now resyncing. I have data backed up to an External 4TB drive for safety. I replaced 1 drive on Saturday then the 2nd 3TB went in today. I panicked when I did the 1st one because I thought I had lost all data after a resync, a reboot and everything was OK. So I now have 2 x 2TB Reds and 2 x 3TB Reds installed. Regards Simon
I totally agree for the backup. At least two locations (1 local, 1 remote) is a bare minimum. I personally have up to 5 copies of critical data, but 3 is enough is the vast majority of cases.
You have to protect yourself from failure, surge, theft, but also any catastrophic event (flood, earthquake...) and of course human error. And that's only basic risks we could find much more. So I would go with raid5 and a good backup system. If you have the ability to get a spare drive as big as your biggest drive (3TB I think), this would be a good thing to do too, as this would speed up the drive replacement by a few days (the time for the manufacturer to deliver you a new disk).
No problem. Disks from the same batch failing the same week, this happens. Having a spare makes you rebuild the raid within 2 days and lowers the risk of having two simultaneous failures. Whereas if you go the normal road you may have to wait more than a week before the raid is rebuilt (assuming 4 days transit time, 1 day for calling support and 2 days to rebuild the raid). I told you to get the largest one because x-raid won't let you plug a smaller drive, so if one of the 3Tb fails you would need a size equal or greater than that; If this is a 2Tb, a 2Tb drive would of course do the trick, but there is no point of having two spare disks of different size in this case. Of course you could go with raid6, but on a 4-bay NAS I believe this is not a good option, on a 6-bay maybe. That's why I would stick to raid5, you get the convenience of x-raid and you only lose the space for one disk. As I said, I would bet on the backup more than on the fault tolerance. RAID is a great tool, but consider it as a "makes life easier" thing, it lets you upgrade your drives, spares transfer time if a drive fails (you don't have to recreate the volume and copy the data back), speed up the disks... But in the event of a failure, you want to have a plan B (if you need to factory reset the NAS for example).
When you know you can rely on your backups, life is easier. You can actually erase, reinstall anything without ever thinking of your data.
