time I move the cache drives. 4 cache drives sit on Asus Hyper M.2 V2 PCIe card. When I moved this card from PCIe slot to another, I get this error this message. Yes, I have set the Asus card was moved to, to 4x4x4x4. This time did a startup with it. I restartet the server, all 4 drives was there, only one in the cache pool. Trying to add the 3 drives, I was warned that they would be deleted. Then I restartet with all drives in the cache pool without starting the Array. When restarted the error message occurred. 

 

This tend to happened every time I move the Asus Card. 

 

maxx-diagnostics-20200226-0053.zip

 

Happy for any help. 

 

 

Cheers,

 

 

Frode

 

 

 

 

Asus C621E Sage/BMC | dual Xeon Silver 4116 | Samsung 4 x 32GB DDR4-2933 RDIMM | 4 x Corsair Force MP510 (960GB) NvME ssd on Asus Hyper M.2 Card V2 l | 4 x WD and Seagate hdd l Sapphire Pulse Radeon RX 580 8GB l Samsung 970 Pro in M.2 port l Asmedia PCIe USB card

I can't why some devices are losing the assignments, is the log from a boot right after just moving the M.2 card?

 

Still as a workaround you can do this:

 

Stop the array, if Docker/VM services are using the cache pool disable them, unassign all cache devices, start array to make Unraid "forget" current cache config, stop array, reassign all cache devices, re-enable Docker/VMs if needed, start array.

 

Alternatively you can also do a new config and reassign all devices, then check parity is already valid before starting the array.

 

On 2/26/2020 at 12:34 AM, JorgeB said:

Stop the array, if Docker/VM services are using the cache pool disable them, unassign all cache devices, start array to make Unraid "forget" current cache config, stop array, reassign all cache devices, re-enable Docker/VMs if needed, start array.

 

Beast. You saved me a huge headache. Thank you!

This also worked for me.  I had an 8TB drive connected as cache, but wanted that as a spare.  I already had a 256GB M.2 drive that was free.  I bought a 256MB SSD drive so that I could use RAID1 for the cache, and keep the 8TB drive as a spare.  I powered down the array, configured everything in hardware, brought the system back up and configured the two SSD drives as a cache pool. 

 

Got the same error for the two cache drives: too many missing/misplace drives.  (Not sure whether this was caused by the new SSD was not formatted - the M.2 was formatted for cache, as I had used it previously for cache.)  I did not have any dockers/VMS. 

 

I stopped the array, removed the two SSDs from cache so there was no cache/pool, then started everything.  Stopped the array, added back in the two SSDs in the cache/pool, then restarted the array.  This worked.

Also worked for me. 100% of my problems with Unraid have been the buggy AF btrfs implementation. Have lost cache drives 3 times this year, despite the drives actually being fine. Retire them to a windows machine as a cache and they still work fine with 0 disk errors. Something is borked in either unraid or btrfs that keeps causing the BTRFS pool devices to become unmountable... 

13 hours ago, Sh0dan said:

Something is borked in either unraid or btrfs that keeps causing the BTRFS pool devices to become unmountable... 

One thing that frequently makes issues worse than they could be is the lack of pool monitoring, see here to be notified as soon as there's a problem with a pool so you can act before it's too late.