35.2 Getting Information about Logical Volumes
As an example of using LVM with Ubuntu we will work through an example of adding space to the / file system of a standard Ubuntu installation. Anticipating the need for flexibility in the sizing of the root partition (assuming, of course, that LVM partitioning option was selected during the Ubuntu installation process), Ubuntu sets up the / file system as a logical volume (called root) within a volume group called vgubuntu. Before making any changes to the LVM setup, however, it is important to first gather information.
Running the mount command will output information about a range of mount points, including the following entry for the root filesystem:
/dev/mapper/vgubuntu-root on / type ext4 (rw,relatime,errors=remount-ro)
Information about the volume group can be obtained using the vgdisplay command:
# vgdisplay
--- Volume group ---
VG Name vgubuntu
System ID...
