Around noon today my Unraid server became very unstable, not sure why I attached Diag file. Any Help is appreciated.

 

I see a lot of ATA15.-- hard resetting link errors and BTRFS Read error's corrected.

tower-diagnostics-20181018-2028.zip

Check connections on cache2

You're having hardware errors with multiple cache devices:

 

Oct 18 20:26:49 Tower kernel: BTRFS info (device sdl1): bdev /dev/sdl1 errs: wr 2794320, rd 0, flush 2687891, corrupt 0, gen 0
Oct 18 20:26:49 Tower kernel: BTRFS info (device sdl1): bdev /dev/sdm1 errs: wr 15852081, rd 849677, flush 0, corrupt 0, gen 0

With SSDs these are usually cable/connection related, though most of your pool devices are on a controller with a port multiplier, and those are not recommended since they can have connection/timeout issue.

I removed that cache device at this point and the server is stable.  I have a multiplier card is there a sata card that you would recommend or do you think this is a non standard way of setting up multiple drives?

Any LSI with a SAS2008/2308/3008 chipset in IT mode, e.g., 9201-8i, 9211-8i, 9207-8i, 9300-8i, etc and clones, like the Dell H200/H310 and IBM M1015, these latter ones need to be crossflashed.

 

Note that these should be used with disks since they don't support trim, use the onboard SATA ports for the SSDs.