Good Morning All,

Just had a funny one on my unraid server.  Noticed PLEX had stopped responding, so logged onto my unraid server, and UNraid was alerting saying my NVME cache drive was missing: 

Unraid Cache disk message: 25-11-2020 03:19
Warning [HOMENAS4] - Cache pool BTRFS missing device(s)
Samsung_SSD_970_EVO_Plus_1TB_S4EWNMFN818406F (nvme0n1)

 

The drive was still listed in the dashboard, but was set as spundown (grey not green) - it wouldnt spin up, and it looks to have been set as read only.  I collected the logs, reboot didnt fix the issue (the drive was now no longer listed at all), but a shutdown and poweroff/on of the system worked, the drive was now show, but i had to stop the array and add it back in as the cache drive.  I am guessing maybe faulty hardware - the server had been up for 15 days with no issues prior to that.

Could someone please have a look at the diag logs to see why this happened?

homenas4-diagnostics-20201127-0924.zip

This can sometimes help:

 

Some NVMe devices have issues with power states on Linux, try this, on the main GUI page click on flash, scroll down to "Syslinux Configuration", make sure it's set to "menu view" (on the top right) and add this to your default boot option, after "append" and before "initrd=/bzroot"

nvme_core.default_ps_max_latency_us=0

Reboot and see if it makes a difference.

thanks, will give this a try