Installation manual

Small Capacity System Disks
H.1 Limited Space Support
H.1.2 Configurations Affected
The RZ24 disk is now too small for the full OpenVMS VAX Version 7.3 and
DECwindows Motif for OpenVMS VAX kits, regardless of the user’s configuration.
Slightly larger disk devices need to be closely monitored, depending on the system
environment and user configuration.
The general disk space guideline for OpenVMS VAX plus DECwindows Motif for
OpenVMS VAX Version 1.2-6 is a system disk of at least 300 megabytes (or about
614,400 disk blocks). For nonworkstation, single-user systems, this guideline
can be reduced to 150 to 200 megabytes because DECwindows support is not
necessary. For timesharing systems, a larger disk is usually necessary due to the
need for many layered products and applications. For OpenVMS Cluster systems,
a larger system disk capacity is also usually required. Refer to the Compaq
OpenVMS Cluster Software, SPD 29.78.19 for details.
For specific information about disk space requirements and supported system
disks, refer to the Compaq OpenVMS Operating System for Alpha and VAX,
Version 7.3 SPD 25.01.63.
While the absolute minimum disk space requirements can make base system
support available, layered products, applications, and user files usually make it
necessary to manage even large capacity system disks carefully. Therefore, some
of the following techniques and ideas can be useful for a broader range of users
than can be listed by hardware type.
H.1.3 Dealing with a Small System Disk
You can solve small system disk configuration problems in three ways:
• Upgrade your hardware to a larger capacity disk device.
• Add additional hardware disk devices (one or more) to the system and
redistribute the software contents.
• Reduce the software contents on the existing disk device.
Upgrading hardware might have the highest monetary cost, but has the benefits
of a full environment and the simplest and fastest upgrade mechanism. Adding
additional hardware (or using existing extra hardware) can require less
money, but requires more time and effort for setting up and maintaining the
environment. Reducing the software contents requires the lowest capital expense
but, by necessity, removes some features, documentation, or capabilities.
If your major constraint is fiscal, you might want to investigate the tailoring
recommendations first. If time or simplicity are more important, you might want
to purchase a larger system disk.
H.2 Tailoring Considerations
Most of this appendix describes the mechanisms for reducing the software
contents on the existing disk device, mostly by tailoring. There are also some
hints for multiple disk systems. There is nothing specific to recommend for
upgrading the hardware device, except that moving up in a single large increment
is much more effective than several smaller ones.
The target device in the following sections is the RZ24 disk, which has 209
megabytes of disk space. However, you can use these methods on any system that
is tight on system disk space.
H–2 Small Capacity System Disks