Creating and Managing Shadow Sets Using DCLCommands
This chapter describes how to create, mount, dismount, anddissolve shadow sets using interactive DCL commands. It also describeshow to use the DCL command SET DEVICE to specify management attributes forshadow set members located at different sites in a multiple-siteOpenVMS Cluster system. In addition, it describes how to use theDCL command SHOW DEVICE and the lexical function F$GETDVI to access currentinformation about the state of shadow sets.
Volume Shadowing for OpenVMS improves data availability byensuring that corresponding logical block numbers (LBNs) on multipledisk volumes contain the same information. Upon receiving a commandto mount or dismount disks in a shadow set, the volume shadowingsoftware may need to reconcile data differences and ensure thatcorresponding LBNs contain the same information.
An understanding of the copy and merge operations used fordata reconciliation is essential to the discussions in this chapter.Therefore, you may find it helpful to refer to Ensuring Shadow Set Consistency to understand how Volume Shadowing for OpenVMSensures data availability and consistency during changes in shadowset membership.
HP Volume Shadowing for OpenVMS
