I have experienced problems with my TrueNAS ZFS pools lately. To begin with I received I/O faults on some disks that I have replaced because I was thinking that does have been faulty, but now I’m getting Degraded state on mirrored pool with other drives quite often especially during heavy read/write sessions. Interesting is also that the fault resets itself after a while.
Besides the hard drives that I suspected faulty I have replaced my LSI 3900-8i HBA card and the cables with new ones. I have also relocated the PCI position of controller card to new PCI slot on the mother board. I’m running TrueNas in esxi environment and I have assigned 6 cores of Intel Xeon E5-2609, and 64GB of RAM to the VM that TrueNas is operating in. I have also increased the speed of the fans in my HP ProLiant ML350 gen9 to ensure sufficient cooling. The only ides that I still need to check is the power supply cables to the SATA drives.
I appreciate if anyone have any experiences or ides?