HP NetServer AA 4000 Manual page 337

Chapter 14
IOPn.MtcScsiP status: DISKn has had SCSI tagged queuing disabled. This disk type may have exhibited problems
with SCSI tagged queuing. This feature is disabled to prevent corruption problems.
Variables n – the disk number; for example, DISK0, DISK1, DISK2
Severity Warning
Description Some disk controllers may exhibit problems when certain SCSI features are used. HP
NetServer AA software attempts to disable certain SCSI features for disk controllers that are
suspected of not handling them properly. The SCSI feature "tagged queuing" was disabled for
this controller. Use of "tagged queuing" permits a disk controller to accept multiple SCSI
requests and reorder their execution for optimal performance.
Action No action is required.
IOPn.MtcScsiP status: DISKn has had write cache disabled. This disk type may have exhibited problems with write
cache. This feature is disabled to prevent corruption problems.
Variables n – the disk number; for example, DISK0, DISK1, DISK2
Severity Warning
Description Some disk controllers may exhibit problems when certain SCSI features are used. HP
NetServer AA software attempts to disable certain SCSI features for disk controllers that are
suspected of not handling them properly. The SCSI feature write cache was disabled for this
controller. Use of write cache permits the disk controller to respond with a success status for
write requests before the data is actually written to disk. The cached data is later written to disk
during a more optimal time.
Action No action is required.
IOPn.MtcScsiP status: DISKn has read cache disabled by default.
Variables n – the disk number; for example, DISK0, DISK1, DISK2
Severity Informational
Description The SCSI disk controller has read cache disabled by default. This may have undesirable
performance consequences. Unless the disk controller has had problems using read cache,
Marathon recommends that the read cache feature be enabled. Use of read cache permits the
disk controller to first check its cache before attempting to read the requested data from disk.
If the requested data is found in cache, the controller will use the cached data and will not read
the data from disk.
Action Consider enabling read cache if the controller has not exhibited problems with read cache in
the past. See the documentation that came with the disk for details.
MtcScsiP and MtcScsiR Messages
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