0

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.

t3mp
  • 111
  • 2

1 Answers1

2

"COMPARE AND WRITE" opcode usually means that your writing queue is continuously growing because of low disk write performance. The reason for such behavior may be a very highly loaded OS (Synology DSM) or faulty disk drive assuming that network connection from your ESX host to NAS is OK. First of all check CPU/RAM usage on your Synology box. Also check the S.M.A.R.T status and health of your disk drives. That should help you to find the root cause of the problem.

Net Runner
  • 5,626
  • 11
  • 29