Technical data

Managing Storage Media
9.6 Setting Up Disk Volume Sets
• Enter the MOUNT/BIND command only once to bind a volume set; thereafter,
the volume set association is recorded on the volumes. (See Section 9.5 for
details.)
• Once you bind two or more volumes into a volume set, you cannot separate
them. The only way to separate a volume set is to use the Backup utility
(BACKUP) to copy sets of directories selectively. (See Section 11.13 for more
information.)
When you mount a disk volume set, the volume label specified in the list must
correspond to a device name in the same position in the device name list.
You can bind two or more disk volumes into a volume set. The first volume in the
set is called the root volume. Each volume in the set is identified by a volume
number relative to the root volume, which is always relative to volume 1.
A disk volume set has a single directory structure. The master file directory
(MFD) is on the first volume in the set.
When a disk volume set is on line and mounted, you can access all files and
directories in the set by specifying either of the following names:
• Device name of the device on which the root volume is mounted
• Logical name assigned to the volume set when it was mounted
9.6.1.2 Using the /BIND Qualifier
Use the /BIND qualifier with the MOUNT command to create a disk volume set
in the following format:
MOUNT/BIND=volume-set-name
where:
volume-set-name Specifies a 1- to 12-alphanumeric-character name identifying the
volume set.
The volume set name must be different from all volume labels within the set, and
all labels in the set must be unique.
The /BIND qualifier identifies a volume set by assigning it a volume set name
that applies to all volumes in the set. The qualifier also identifies the root volume
and creates the directory structure for the volume.
When you create files on a volume set, the file system allocates space for the files
anywhere on the set, wherever the most space exists. When existing files on any
volume are extended, extension occurs on the same volume unless the volume is
physically full.
You can add new volumes to a volume set whenever additional space is needed.
You can, for example, bind all disk volumes that are mounted into a volume set
on a daily basis. Since this set contains all user file directories, users do not need
to specify device names in file specifications to access files on any volume in the
volume set. In fact, the physical location of a file is of no concern to users of the
system.
Note
Do not bind your system disk into a volume set. System software updates
and optional product installations do not support volume sets. If certain
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