My RN214 has four 6TB drives in it in RAID 5 (so 18TB of usable space), and recently it randomly switched to read only mode. I checked the logs in the web GUI and it shows the "Volume: The volume data encountered an error and was made read-only. It is recommended to backup your data." message. My research on the forums here seems to indicate that resetting it (after backing up all of the 15TB of data) is pretty much the only option, but I wondered if maybe there are any other options, including upgrading the drives to larger storage and having it rebuild the RAID array one disk at a time.
Anyone more knowledgeable in this sort of stuff? I don't have enough capacity in the other drives that I have on hand to back up the data that the RN214 is storing on site, and would REALLY prefer not to have to download the 15TB of data from my online backups that live in the cloud.
I know I may get asked about the logs - I downloaded them but don't know which file will contain the pertanent information with regards to the error I'm seeing. If you can tell me I can copy and paste that info here as well.
Normally the volume goes read-only when the system finds btrfs (file system) corruption. You should be able to find btrfs errors reported in system.log and kernel.log. These file system errors are often (but not always) linked to disk errors (which might also be in those logs). If you have ssh enabled, you might also be able to see recent disk errors using smartctl -x
You could try paid Netgear support (my.netgear.com). This could require paying for data recovery ( https://kb.netgear.com/69/ReadyNAS-Data-Recovery-Diagnostics-Scope-of-Service ), but in some cases the normal support might be able to resolve it. It could be cheaper to just purchase some disks (two 10 TB WD EasyStores would cost you about $450 US) - and paid support might not be able to repair your volume w/o offloading data anyway.
If you want the mods ( @JohnCM_S or @Marc_V ) to look at your logs, then you should send them a download link to the full log zip file. Send that using the private message (PM) facility of the forum by clicking on the envelope icon on the upper right of the forum.
I don't have enough capacity in the other drives that I have on hand to back up the data that the RN214 is storing on site, and would REALLY prefer not to have to download the 15TB of data from my online backups that live in the cloud.
Personally I use cloud backup for disaster recovery (keeping local backups for other scenarios). Might be something to consider.
Would it be possible to create a local backup of some of the shares, and restore the others from the cloud?
