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We commonly use the word ``partition'' to refer to two concepts:
Just as the noun ``partition'' refers to both a portion of the disk and a subdivision of that partition, the verb ``partition'' also points to two steps:
The phrase ``partitioning the disk'' is used by many people
to refer to both steps.
To avoid confusion, we differentiate between the two
by using the terms ``partition the disk'' and ``defining slices.''
Additional information about partitions and slices is available in
vtoc(7).
A single hard disk can support multiple operating systems but not in the same space on that disk. You have the choice of either using all the space on your hard disk for UnixWare or dividing the hard disk into a maximum of four segments, called partitions. Each partition can hold a separate operating system. For example, you could have a UnixWare system partition, a SCO OpenServer system partition, an OS/2 partition, and a DOS partition.
Carefully consider the type, number and size of partitions you want on your system before creating them; changing them later requires that existing partitions and data be destroyed. When creating partitions, note that:
Your first opportunity to create partitions comes during the initial system load (ISL) of your UnixWare system. At that time, you can define partitions and slices for each of two hard disks, a primary and a second hard disk. When you install UnixWare on an existing system you are asked whether you want to keep the existing partitioning scheme (the default scheme) or create a new one. If you are installing on a new machine, the default scheme is one partition (partition #1), which uses 100 percent of each disk for UnixWare.
If you add a hard disk after ISL, use the
diskadd(1M)
command to create the partitions and slices.
See
``Adding hard disks''.
Changing the number or size of hard disk partitions destroys existing partitions and data on the disk being re-partitioned. If you must change your hard disk partitions, be sure to back up your data first (back up each partition on the disk).
Only one partition can be active at a time. There are two ways to change the active partition.
Starting UnixWare
...
message appears, you can interrupt the boot process and invoke the
Boot Command Processor (BCP) by pressing any key.
Then, at the [boot]
prompt, you can enter parameters to specify
which partition to boot from.
See boot(4) for more information about boot parameters.
Each VTOC on a UnixWare partition can contain
up to 184 slices (numbered from 0 through 183).
Slices can be allocated as filesystems, swap area(s) or dump slices.
The slices on your hard disk(s) are initially assigned as part of the initial system load (ISL) process.
If you add a hard disk after ISL, use the diskadd(1M) command to create the slices. See ``Adding hard disks''.
The following information from the Getting Started Guide provides guidelines for defining slices and filesystems.
This filesystem is required, and can be of type vxfs (default, recommended) or ufs.
The filesystem type must be bfs.
The default size provided should be adequate for your system, and must
not, in any case, exceed 128MB.
The default swap value is adequate for most systems; you may consider increasing its size if you are running large applications which consume system resources. If you do increase the size of your swap slice, you decrease the amount of space on your disk to store user data. See ``Adding swap space'' for information about increasing swap space.
This slice is not enabled by default, and in most cases is not necessary. If you create a dump slice, it should be as large as your system's RAM.
These filesystems should be configured as the same type you chose for the root filesystem. If you do not enable these filesystems, they are created as subdirectories of the root filesystem.
This filesystem should be configured as the same type you chose for the root filesystem. If you do not enable this filesystem, /var is created as a subdirectory of the root filesystem.
This filesystem can be configured as memfs, in which case all files and directories are automatically flushed during each reboot, or as the same type you chose for the root filesystem.
This filesystem must be configured as memfs. All files and directories are automatically flushed during each reboot. If you do not enable this filesystem, /var/tmp is created as a subdirectory of the root filesystem.
If you plan on installing the Online Data Manager, you should enable this volume as type slice with a size of 1MB.
Some devices, such as SCSI hard drives, provide their own mapping scheme. If you have such a device, set this slice to a small size and do not enable it on the second disk.
After your system has been in operation for a while determine whether the allocation of slices (as reflected in the VTOC definition) is appropriate. Does it meet the needs of your users? Consider whether system performance might be improved by a larger number of smaller filesystems than you currently have, or by allocating filesystems to different hard disks. Begin by analyzing how well your system performs with the existing filesystem arrangement. See ``Managing system performance'' for a description of the sar(1M) command that evaluates performance.
If you frequently get console messages warning of insufficient memory, the amount of main memory or the swap area configuration may be insufficient to support users' demands. Before adding more main memory, try expanding the swap area. See ``Adding swap space''.
Before you reassign slices on a boot disk, do a full system backup. To reassign slices on the boot disk, you must reinstall UnixWare.
Use the disksetup(1M) command to reassign slices on disks other than the boot disk.