Jane.doe at 18:25, 13 December 2019

2019-12-13T18:25:27Z

← Older revision		Revision as of 18:25, 13 December 2019
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	An '''allocation class''' is a number that serves as part of a [[Device Name\|device name]] to provide unique and unchanging names to uniquely identify shared devices, files, and data. Allocation classes are required in [[Cluster\|OpenVMS Cluster]] configurations where storage devices are accessible through multiple paths. Without the use of allocation classes, device names that relied on node names would change as access paths to the devices change.		An '''allocation class''' is a number from 1 to 255 that serves as part of a [[Device Name\|device name]] to provide unique and unchanging names in the form $allocation-class$device-name to uniquely identify shared devices, files, and data. Allocation classes are required in [[Cluster\|OpenVMS Cluster]] configurations where storage devices are accessible through multiple paths. Without the use of allocation classes, device names that relied on node names would change as access paths to the devices change.

			Prior to [[OpenVMS Version 7.2]], all nodes with direct access to the same multipathed device were required to use the same nonzero value for the node allocation class. [[OpenVMS Version 7.2]] introduced the [[MSCP_SERVE_ALL]] system parameter, which can be set to serve all disks or to exclude those whose node allocation class differs.

			=Port Allocation Class=
			OpenVMS Version 7.1 introduced a port allocation class, which is specific to a single interconnect and is assigned to all devices attached to that interconnect. Port allocation classes
			were originally designed for naming SCSI devices. Their use has been expanded to include additional devices types: floppy disks, PCI RAID controller disks, and IDE disks. The use of port allocation classes is optional.

	=See also=		=See also=
	* {{Template:SysmanI}}		* {{Template:SysmanI}}
	* {{Template:Cluster}}		* {{Template:Cluster}}

Jane.doe: Created page with "An '''allocation class''' is a number that serves as part of a device name to provide unique and unchanging names to uniquely identify shared devices, files, a..."

2019-12-13T18:19:18Z

Created page with "An '''allocation class''' is a number that serves as part of a device name to provide unique and unchanging names to uniquely identify shared devices, files, a..."

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An '''allocation class''' is a number that serves as part of a [[Device Name|device name]] to provide unique and unchanging names to uniquely identify shared devices, files, and data. Allocation classes are required in [[Cluster|OpenVMS Cluster]] configurations where storage devices are accessible through multiple paths. Without the use of allocation classes, device names that relied on node names would change as access paths to the devices change.

=See also=
* {{Template:SysmanI}}
* {{Template:Cluster}}

Allocation Class - Revision history

Jane.doe at 18:25, 13 December 2019

Jane.doe: Created page with "An '''allocation class''' is a number that serves as part of a device name to provide unique and unchanging names to uniquely identify shared devices, files, a..."