I have error iSCSI target (Synology DS1813+) used as NAS:
Jan 19 12:03:55 SRV1 kernel: [23311947.266497] iSCSI: iSCSI: EPIO[/volume1/@iSCSITrg/iSCSI_3_Extent_LUN-LUN1_000], opcode[89], error(-65539), pos(10578610176)
By wiki: SCSI command this is command: "COMPARE AND WRITE". But that mean this error? pos?
During this error on ESXi (iSCSI iniciator) I/O latency increased.
Device "xxx" performance has deteriorated. I/O latency increased from average value of 29890 microseconds to 604191 microseconds. warning
Long/Shot SMART test status is OK.