Installation guide

This command creates the volume group special device ﬁle, which

is a direct connection between the volume group and the LVM

driver code. The volume group special device ﬁle must be a

character (c) device; it must use one of three predeﬁned major

device numbers, in this case 16; and it must have a minor device

number of 0.

d. Create the volume group and populate it with the physical

volumes you created with the pvcreate commands:

# vgcreate /dev/vg01 /dev/rz1g /dev/rz2g

Creating /etc/lvmtab.

Volume group /dev/vg01 has been successfully created.

This command creates the /dev/vg01 volume group that has the

members /dev/rz1g and /dev/rz2g. The /etc/lvmtab ﬁle

contains information that allows the LVM software to access the

physical volumes that compose its volume groups after a system

reboot.

e. Create the logical volume:

# lvcreate -s y -n logvolmir /dev/vg01

A logical volume with name "logvolmir" will be created.

Logical volume "/dev/vg01/logvolmir" has been successfully

created with minor number 1.

The lvcreate command creates a logical volume name,

logvolmir.

f. Extend the logical volume to encompass all the physical extents of

one physical volume. In this example, 63 is the total number of

physical extents in the physical volume /dev/rz1g. The

vgdisplay command lists the number of physical extents

available on each volume.

Specify a logical extent for the logical volume by using the

lvextend command:

# lvextend -l 63 /dev/vg01/logvolmir /dev/rz1g

Logical volume "/dev/vg01/logvolmir" has been

successfully extended.

The -l option extends the logical volume so that it encompasses

63 physical extents. The ﬁrst argument to the command,

/dev/vg01/logvolmir, names the logical volume. The second

argument, /dev/rz1g, speciﬁes that the logical extents are

assigned to the physical extents on the /dev/rz1g physical device.

4. Mirror the logical volume on the /dev/rz2g device:

# lvextend -m 1 /dev/vg01/logvolmir /dev/rz2g

The newly allocated mirror is now being synchronized.

5–6 Migrating Your ULTRIX System and Network Environment