Installation guide

Specify the device with its directory name (/dev) followed by the raw
device name, drive number, and partition a or c. You can also specify the
disk unit and number, such as rz1.
An example of using the disklabel command to view a disk label follows:
# disklabel −r /dev/rrz3a
type: SCSI
disk: rz26
label:
flags:
bytes/sector: 512
sectors/track: 57
tracks/cylinder: 14
sectors/cylinder: 798
cylinders: 2570
rpm: 3600
interleave: 1
trackskew: 0
cylinderskew: 0
headswitch: 0 # milliseconds
track-to-track seek: 0 # milliseconds
drivedata: 0
8 partitions:
# size offset fstype [fsize bsize cpg]
a: 131072 0 4.2BSD 1024 8192 16 # (Cyl. 0 - 164*)
b: 262144 131072 unused 1024 8192 # (Cyl. 164*- 492*)
c: 2050860 0 unused 1024 8192 # (Cyl. 0 - 2569)
d: 552548 393216 unused 1024 8192 # (Cyl. 492*- 1185*)
e: 552548 945764 unused 1024 8192 # (Cyl. 1185*- 1877*)
f: 552548 1498312 unused 1024 8192 # (Cyl. 1877*- 2569*)
g: 819200 393216 unused 1024 8192 # (Cyl. 492*- 1519*)
h: 838444 1212416 4.2BSD 1024 8192 16 # (Cyl. 1519*- 2569*)
You must be careful when you change partitions because you can overwrite
data on the file systems or make the system inefficient. If the partition
label becomes corrupted while you are changing the partition sizes, you can
return to the default partition label by using the disklabel command
with the −w option, as follows:
# disklabel -r -w /dev/rrz1a rz26
The disklabel command allows you to change the partition label of an
individual disk without rebuilding the kernel and rebooting the system.
Use the following procedure:
1. Display disk space information about the file systems by using the df
command.
2. View the /etc/fstab file to determine if any file systems are being
used as swap space.
3. Examine the disk’s label by using the disklabel command with the
−r option. Refer to the rz
(7) and ra(7) reference pages and to the
/etc/disktab file for information on the default disk partitions.
4. Unmount the file systems on the disk whose label you want to change.
7–28 Administering the UNIX File System