6.4.6 Notes about SCSI reservation for shared disk
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It is not possible to create multiple partitions on a single physical device so that each server can use a different partition.
SCSI reservation is performed for each physical device. If separate partitions are used by the different servers, the disk cannot be protected because SCSI reservations cannot be obtained correctly.
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The same names must be specified in the same order on each host for the device names specified in the scsi_device and dmmp_device operands in the server environment definition. If the specified names or their specification order differ between hosts, SCSI reservations might not be obtained correctly.
In the case of a redundant configuration using HDLM, the order in which the device names are specified in the scsi_device operand must be the same on each host. If the same disk is used for all hosts in a hot-standby configuration, different names can be specified.
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If you use LVM, in the scsi_device and dmmp_device operands, you must specify all device names that correspond to the device file names for the physical volumes that make up each volume group specified in the disk operand.
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If you use a disk or partition that does not use LVM, in the scsi_device and dmmp_device operands, specify the device name that corresponds to the logical unit that contains the file system specified in the fs_name operand. If you create multiple partitions (file systems) on one logical unit, specify the device name that corresponds to the logical unit. Do not specify the same device name multiple times.
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For the shared disks corresponding to the logical devices specified in the scsi_device and dmmp_device operands, do not use an LVM mirror or Linux standard software RAID (md).