This procedure describes how to set a new volume group and file systems on a Red Hat Enterprise Linux system.

First, we'll need to make sure that there is storage available on the system that can be allocated to a new volume group. For this purpose, run the lsblk command:

# lsblk | grep disk

In the output, for example, you may see:

# lsblk | grep disk
fd0       2:0      1    4K  0 disk
sda       8:0      0   60G  0 disk
sdb       8:16     0    5T  0 disk

In the example above, the system has two SCSI devices (that start with "sd"), called sda and sdb. Device sda is 60 GB, and device sdb is 5 TB.

Next, run this command:

# lsblk -a

It will provide you with a tree-like output showing all the disks available on the system, and any partitions (listed as "part") and logical volumes (listed as "lvm") configured on those disks. For the sake of this example, we'll assume that on device sdb there are no partitions and or logical volumes configured, and thus is available.

Also, for the sake of this example, we'll assume that we'll want to set up a few file systems for an Oracle environment, called /u01, /u02, /u03, /u04 and /u05, and that we'll want to have these file systems configured within a volume group called "oracle".

List the volume groups already configured on the system:

# vgs

Make sure there isn't already a volume group present that is called oracle.

Now, let's create a new volume group called oracle, using device sdb:

# vgcreate oracle /dev/sdb
  Physical volume "/dev/sdb" successfully created.
  Volume group "oracle" successfully created

We can now use the "vgs" and "pvs" commands to list the volume groups and the physical volumes on the system. Note in the output that you now can see that a volume group called "oracle" is present, and that disk /dev/sdb is configured in volume group "oracle".

Now create the logical volumes. A logical volume is required for us to create the file systems in later on. We'll be creating the following logical volumes:

• u01lv of 100 GB for the use of the /u01 file system
• u02lv of 1.5 TB for the use of the /u02 file system
• u03lv of 1.5 TB for the use of the /u03 file system
• u04lv of 1.5 TB for the use of the /u04 file system
• u05lv of 300 GB for the use of the /u05 file system

Run the following commands to create the logical volumes. You may run the "lvs" command before, in between and after each command to see your progress.

# lvcreate -n u01lv -L 100G oracle
# lvcreate -n u02lv -L 1.5T oracle
# lvcreate -n u03lv -L 1.5T oracle
# lvcreate -n u04lv -L 1.5T oracle
# lvcreate -n u05lv -L 300G oracle
# lvs | grep oracle
  u01lv oracle -wi-a----- 100.00g
  u02lv oracle -wi-a-----   1.50t
  u03lv oracle -wi-a-----   1.50t
  u04lv oracle -wi-a-----   1.50t
  u05lv oracle -wi-a----- 300.00g

Now it's time to create the file systems. We'll be using the standard XFS type of file system:

# mkfs.xfs /dev/oracle/u01lv
# mkfs.xfs /dev/oracle/u02lv
# mkfs.xfs /dev/oracle/u03lv
# mkfs.xfs /dev/oracle/u04lv
# mkfs.xfs /dev/oracle/u05lv

And now that the file systems have been created on top of the logical volumes, we can mount the file systems. To ensure that file systems are mounted at the time that the system boots up, it's best to add the new file systems to file /etc/fstab. Add the following lines to that file:

/dev/oracle/u01lv      /u01     xfs      defaults,noatime 0 0
/dev/oracle/u02lv      /u02     xfs      defaults,noatime 0 0
/dev/oracle/u03lv      /u03     xfs      defaults,noatime 0 0
/dev/oracle/u04lv      /u04     xfs      defaults,noatime 0 0
/dev/oracle/u05lv      /u05     xfs      defaults,noatime 0 0

Make sure the folders of the mount points exist by creating them:

# mkdir /u01
# mkdir /u02
# mkdir /u03
# mkdir /u04
# mkdir /u05

Now mount all the file systems at once:

# mount -a

And then verify that the file systems are indeed present:

# df -h | grep u0
/dev/mapper/oracle-u01lv  100G   33M  100G   1% /u01
/dev/mapper/oracle-u02lv  1.5T   33M  1.5T   1% /u01
/dev/mapper/oracle-u03lv  1.5T   33M  1.5T   1% /u01
/dev/mapper/oracle-u04lv  1.5T   33M  1.5T   1% /u01
/dev/mapper/oracle-u05lv  300G   33M  300G   1% /u01

And that's it. The file systems have been created, and these file systems will persist during a system reboot.



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