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External storage must support SCSI-3 PR.
Volume should be configured by LUN(Logical Unit Number) unit. Partitioned volume in a LUN is not supported.If use PrType 3, at least 1GByte LUN is needed for key reservation.

Types of Shared disk resource

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2. Both the shared disk agent and the SCSI reservation agent can read and write data.
However, a SCSI reservation agent intends to protect the shared storage resource, so you are not recommended to use it alone to read and write data.
Thus, a SCSI reservation agent can be used together with a shared storage agent or can use a separate LUN from the shared storage (PrType option). 

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PrType (Persist Type) 1 : Type1 controls 'Write" of LUN. When use this option, shared disk resource can be used as lock disk. (Exclusive Write)
PrType (Persist Type) 3 : Typ3 controls "Access" of LUN. When use this option, exclusive LUN is needed for lock disk. 

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Configuration

SCSI-Lock resource can be configured in 2 ways with shared disk resource. Configuration process changes according to the attribute value of SCSI Lock resource.

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