I run two ESXi 5.5 hosts on whitebox hardware with AHCI controllers and SATA disks.
During times of high disk i/O (e.g. VM backups) I regularly got "SCSI device busy" (sense code 8) errors in vmkernel.log which looked like this:
vmkernel: cpu6:33379)ScsiDeviceIO: 2324: Cmd(0x412e807f9440) 0x2a, CmdSN 0x800100be from world 36324 to dev "t10.ATA_____ST2000NM00332D9ZM175_________________________________Z1X0GSQZ" failed H:0x0 D:0x8 P:0x0 Possible sense data: 0x0 0x0
Since I installed Update 2 (shortly after it was released) I no longer get these errors, even during times of high disk I/O.
I wonder why? Do these errors really no longer occur (because of code changes in the updated ahci driver or somewhere else in VMkernel), or are they just no longer logged, because they are considered uncritical?
Do others with similar hardware configs notice the same?
Is there another way to check whether these errors occur or not?
Can someone from VMware shed some light on this?