Woke up the other day with 500 warning messages that the cache drive was missing. “Failed to access the installed drive. Check SSD M.2 2”
In Storage> Drives - it showed as if the second M.2 drive was just missing. Guess it died after only three years. Since that point, none of the other drives/apps have been accessible and showing “Cache missing”. I ordered an identical replacement (WD Blue M.2 1TB). The other M.2 drive was showing as fine still. Got the drive today and swapped out the bad drive.
After booting up, it now shows two good M.2 drives, but I cannot find a way to “rebuild” the raid. After booting up I am still getting the following errors.
“SSD Cache RAID group ‘2’ is inactive”
“Failed to recover RAID group ‘2’. Storage Pool 256”
On the Cache Acceleration tab, the service is “Off” and greyed out. Under MANAGE menu is Remove and Settings, the other two are greyed out.
Any suggestions as to how to either recover the raid or is it safe/possible to remove the “Raid 2” and start over? If I do the latter, will it impact the access to the drive volumes in any way? At this point if I do have to rebuild, I will probably do a raid 1 configuration just in case the other drive fails in the near future.
So at this point is my best course of action to “Remove” under Manage and then rebuild a new Raid 1 configuration for the two M.2 drives? If I do that (start new), will it have impacts on the three volumes that currently show “Cache Missing”? Will I need to do anything else to get access to those volumes?
Maybe not all but some is likely lost. Any data in the cache that hasn’t been flushed to the main drives is now gone.
Hopefully you have backups.
I took the advice of Dolbyman and eliminated using the cache as it doesn’t provide a lot of value. And caching really kills the SSD drives. I found the SSD drive I was using for a cache to have used 15% of its lifespan in just a few months of use.
so, after getting a little sleep, I have a renewed focus on this ‘challenge’.
I have had several external HDs connected and doing a scheduled frequency of backing up the different volumes. I also had a new DAS added 90 days ago and did one big backup (7.5 days). This was due to replacing failed drives in the largest (raid 6) volume. In doing so, I enlarged all six drives to 6x24TB (swap/rebuild, one at a time) over the past set of weeks. I am now in a situation where I need to expand the volume.
Challenge is that I will need to rebuild the current 42TB volume as it will need to be split up into two volumes due to size max vs. file quantity max configurations while keeping it raid 6. I guess that at this point, I need to determine if I am now needing to just blow away the three volumes in place, rebuild them in new configurations (utilizing the extra drive space), and then doing a restore of data from the externals from the most recent backups. Haven’t had to do all of this before, and need to find the best way to ensure better long term design. I guess I will no longer us the two 1TB M.2 drives as a cache anymore either.
For your 42TB system, you may want to consider going to QuTS Hero. In Hero, your shared folders become “volumes” and you can set each one to whatever block size you want. Not sure if that will help you but something to consider.
Regarding the situation you’re facing, I suggest you open a support ticket through our Helpdesk or via the community. Our Support Team will be able to help you resolve it. Thanks!
I do have a experience that my M.2 dead while acting as read cache.
From my memory that after remove the cache from system, the storage volume back to normal, just without a cache. And I am able to build another cache space after replacing the dead M.2.
