HP OpenVMS Systems Documentation

Content starts here Using $MOUNT to Mount Volume Sets
HP Volume Shadowing for OpenVMS: OpenVMS Version 8.4 > Chapter 5 Creating and Managing Shadow Sets with System Services

Using $MOUNT to Mount Volume Sets

When mounting volume sets, always list the volume with the largest storage capacity first. You should name the largest volume first because the volume set and directory information goes on the first volume listed in a MOUNT command line. A small-capacity disk may not have adequate storage for the volume and directory information.

Example 5-3 shows the MACRO-32 statements required to produce a $MOUNT system service item to mount a volume set that contains two shadow sets.

Example 5-3 Item List to Create and Mount a Volume Set

DSA23:  .ASCID /DSA23:/
DSA51:  .ASCID /DSA51:/
MEMBER009:   .ASCID /$4$DUA9:/
MEMBER005:   .ASCID /$4$DUA5:/
MEMBER010:  .ASCID /$4$DUA10:/
MEMBER012:  .ASCID /$4$DUA12:/
MEMBER003:   .ASCID /$4$DUA3:/
MEMBER034:  .ASCID /$4$DUA34:/

        .WORD    SIZE, CODE
        .ENDM    .ITEM

        .ITEM   8, MNT$_SHAMEM, MEMBER009   
        .ITEM   8, MNT$_SHAMEM, MEMBER005
        .ITEM   9, MNT$_SHAMEM, MEMBER010
        .ITEM   5, MNT$_VOLNAM, VOLUME_WORK1  
        .ITEM   6, MNT$_SHANAM, DSA51  
        .ITEM   9, MNT$_SHAMEM, MEMBER012  
        .ITEM   8, MNT$_SHAMEM, MEMBER003
        .ITEM   9, MNT$_SHAMEM, MEMBER034
        .ITEM   5, MNT$_VOLNAM, VOLUME_WORK2   

The following list describes the elements in Example 5-3:

  • Notice that the virtual unit item descriptor for the first volume in the volume set occurs first. This item descriptor specifies DSA23 as the name of the first virtual unit in the volume set.

  • The virtual unit item descriptor is followed by item descriptors for each of the devices or members that are to be represented by the first virtual unit: $4$DUA9, $4$DUA5, and $4$DUA10.

  • The member item descriptors are followed by an item descriptor that specifies the volume label for the first shadow set in the volume set as WORK1.

  • Following the descriptors for the first shadow set in the volume set are similar item descriptors for the second shadow set in the volume set. These item descriptors specify the second virtual unit as DSA51; the devices as $4$DUA12, $4$DUA3, and $4$DUA34; and the volume label as WORK2.

  • The last item descriptor specifies the logical name for the entire volume set as WRKD$.