How To Create LVM Partition

Hello Friends,

 

My friend asked me a query regarding the LVM Creation with a new harddisk. So i thought that it might be helpfull to all my friends using LVM on Linux.

 

To create LVM partition when we have a new hard disk installed on our server/system.

 

STEP 1. fdisk /dev/hdb    // create a partition in second HD

 

Now show the partition table on your system using p command.

 

Command (m for help): p          // show partition table

OUTPUT
Disk /dev/hdb: ---.- GB, xxxxxxxxxx bytes
xxxx heads, xx sectors/track, xxxxxx cylinders
Units = cylinders of xxxxx * xxx = xxxxxxxx bytes
 
Device Boot   Start   End   Blocks   Id   System     
 

// nothing

 

Create a new partition using n option

 

Command (m for help): n     // create partition

Command action
  e    extended
  p    primary partition (1-4)

p    // primary

Partition number (1-4): 1   // partition number

First cylinder (x-xxxxx, default 1):   // First cylinder

Using default value 1  Last cylinder or +size or +sizeM or +sizeK (x-xxxxx, default xxxxx):    // Last cylinder

Using default value xxxxx

 

After creation of new partition we need to see our partition table.

 

Command (m for help):  p   // show partition table

 

OUTPUT
Disk /dev/hdb: xxx.x GB, xxxxxxxxxxxx bytes
xxx heads, xx sectors/track, xxxxx cylinders
Units = cylinders of xxxxxxx * xxx = xxxxxxx bytes
 
   Device Boot Start End      Blocks   Id  System 
  /dev/hdb1      x   xxxxx  xxxxxxxxxx 83  Linux     // created

 

Command (m for help): t      // change partition type

Selected partition 1    // number

Hex code (type L to list codes): L    // show list of type

 

Hex code (type L to list codes): 8e    // Linux LVM

Changed system type of partition 1 to 8e (Linux LVM)
 
Command (m for help): p    // show partition table

 

OUTPUT
Disk /dev/hdb: xxx.x GB, xxxxxxxxxxx bytes
xxx heads, xx sectors/track, xxxxx cylinders
Units = cylinders of xxxxx * xxx = xxxxxxxxx bytes
 
Device Boot Start  End       Blocks         Id      System

/dev/hdb1     x     xxxxx    xxxxxxxx   8e   Linux LVM    // changed

 
Command (m for help):  w    // save and exit

 

STEP 2. fdisk -l /dev/hdb // show status

 

 

STEP 3. Now we need to create Physical Volume

 

pvcreate /dev/hdb1      // create Physical Volume

 

If we need to specify partition size, use command as below

 

pvcreate --setphysicalvolumesize 100G /dev/hdb1

 

 

To display status of Physical volume (Optional)

 

pvdisplay /dev/hdb1        // display status

 

STEP 4. We can change the volume size of Physical volume (Optional)

 

pvresize --setphysicalvolumesize 100G /dev/hdb1

 

STEP 5. To show the physical volume

pvs /dev/hdb1

 

STEP 6.  To Scan the Physical volume

pvscan  /dev/hdb1

 

 

Now we can create Logical Volume, using the following steps.

 

1.     lvcreate –L 10G –n lvm1 vg0

2.     lvdisplay // to display the logical volumes.

3.     lvextend –L 20G /dev/vg0/lvm1

4.      resize2fs /dev/vg0/lvm1   //Most important thing to do in last 

 

Note: Here i have used xxx for any number, depands on the size of the harddisk.