A question about backing up a 12TB (6TB mirrored) G-RAID drive.
I had been planning on purchasing a 6TB external USB drive to back up my G-RAID drive and store at a remote site in case of a catastrophic failure (e.g. flood, fire). I’m wondering though if it is possible to purchase a spare 6TB drive and remove one of the drives in the array as a backup. Then swap this spare intermittently having the array rebuild on each swap. Thinking this would happen once every few months at most. Thoughts?
The unit and a RAID1 device always works best when both drives are present so that the mirror is intact. We don’t recommend the workflow you are trying to use.
You would have to constantly rebuild the entire RAID every time you swapped in a drive which would take many hours.
If you want to do what you’re proposing then the best idea would be to set the RAID as a JBOD and not a RAID1. Then the drives are individual and not tied down to a RAID rebuild. You then would use software to essentially sync your drives together. One such software is ChronoSync.
Thanks, advice is very much appreciated. I’ll likely just use a 6TB
external drive to back up to for this purpose. To be clear, the intent was to ensure two drives were always present aside from the few minutes required to swap a drive. The RAID would have to be rebuilt each time the swap was performed however. I wasn’t sure what stress on the system this would involve, swapping drives so frequently.
How does one initiate the RAID rebuild? I removed a drive intending to try the same workflow, and when I plugged in back in, the configuration utility doesn’t show any options to rebuild. Worse, the utility says it is still in RAID 1 configuration, but I see now that writes are only going to one drive. I noticed Windws thinks there is one drive offline and one online now. When I change the offline drive to Online, it shows up as a second drive, as if the configuration is JBOD, but the configuration utility still thinks it’s RAID1 but not behaving that way. How do I reenable the mirror and rebuild the array without losing data?
The first thing you should do is transfer the data from one of the working drives currently elsewhere in the event that a rebuild goes bad and it doesn’t maintain the data.
When you open the configurator it will let you chose from multiple devices. In the drop down menu it will list your device but have a D added to it. This means Degraded and it is the one that needs to be chosen in order for the Rebuild button to be clickable. Once you have done so it will rebuild.
However if you had ejected it and wrote data to one drive then it is out of sync and this process is the reason I recommended not swapping the drives.
If it won’t let you rebuild or you don’t have the Degraded option you will need to re-create the RAID1 from scratch, configure the unit to RAID0 then back to RAID1 and start over. (This is the reason why I suggested transferring the data elsewhere prior to starting)
Thanks. I can confirm that backing up, switching to RAID0 then back to RAID1 successfully recreated the RAID1 array. It is somewhat unfortunate it never gave me the option to rebuild because the ejected drive never was recognized as bad, but at least I now know what the expected workflow is.
