I have been fighting failing parity checks for a few months now on my unraid server. I looked into each disk, checked smart stats and even thought I had found the culprit hard drive that was causing the issues. I still had it in my array but with no data on it just in case. This all happened just before another set of problems arose. The VMs on my server started acting up, crashing, and eventually when logging into one VM, everything crashed due to memory problems. I ran memtest and discovered that one of my RAM sticks was at issue, and from there determined that it simply wasn’t seated properly. After reseating the RAM, everything started working properly again. Parity checks come back clean, no more kernel panics, and the VMs are running stably. One partially unseated RAM stick caused all those issues.
Just another tech blag