Specifications

CHAPTER 7 High-Availability Configurations with VMware GSX Server
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SCSI Reservation Support
SCSI reservation support is limited by the following:
• You can enable SCSI reservation for SCSI virtual and physical disks. No other type
of SCSI devices can use SCSI reservation in a virtual machine. Specifically, you
cannot enable SCSI reservation for a generic SCSI disk.
Note: VMware supports SCSI reservation when used with preallocated virtual
disks. Support for SCSI reservation with physical disks is considered
experimental. For high-availability configurations, use SCSI reservation with
preallocated virtual disks.
• SCSI disks can be shared via SCSI reservation among virtual machines running on
the same host. This means that the configuration files for the virtual machines
must all be located on the same GSX Server host. However, the disk or disks the
virtual machines are sharing can be located remotely on a different host.
• Even though the virtual disk is a SCSI disk, it can be located on a host running on
an IDE drive. A physical disk must always be a SCSI disk.
• GSX Server virtual machines currently support only the SCSI-2 disk protocol, and
not applications using SCSI-3 disk reservations. All popular clustering software
(including MSCS and VCS) currently use SCSI-2 reservations.