Extend Logical volume using LVM
I am going to extend already created xfs file system using LVM by 1GB.
Currently i have no free space in pv / vg / lv to extend it to the File system.
So i will be adding a new 1 GB disk to the VM first and then extend vg / lv.
Adding disk and making partition is explained here.
Let's continue with our work to extend pv first.
Current pv vg and lv output as below. and you can see i have no space for now.
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| 1.1 Current Physical volume |
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| 1.2 Current Physical volume free space detail |
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| 1.3 Current VG details |
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| 1.4 Current LV details |
I have completed adding disk and got it on the server by scanning the scsi hosts.
Lets proceed creating a new pv using the newly added disk.
Command to create pv - pvcreate
Syntax : pvcreate disk_name
disk_name = /dev/sdc1
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| 1.5 pv create |
Now we can extend our vg vgdata with the newly created pv as shown below,
Syntax: vgextend vgname pvname
vgname = vgdata
pvname = /dev/sdc1
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| 1.6 vg extend |
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| 1.7 new vg details |
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| 1.7 current lv details |
Syntax : lvextend -L +size lvname
size = 1020MiB
lvname = /dev/vgdata/lvdata
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| 1.8 extend lv |
You can see the newly extended size in lvs and lvdisplay command as below
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| 1.9 new lv |
LV size is extended, however this will not be visible to file system yet. we have to resize / grow the file system. I have a xfs file system so i will use xfs_growfs, if you have a older fs like ext4/3/2 you may use resize2fs.
command: xfs_growfs
Syntax : xfs_grow lvname/devicename
lvname = /dev/mapper/vgdata-lvdata
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| 1.10 xfs grow |
Once you have executed xfs_growfs for the file system you can now see the increased size in the df -h output and you can start utilizing the newly available fs.
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| 1.11 Extended xfs filesystem |
This is the best advantage of a LVM, you can grow/extend/increase your file system space online without any need for downtime.
LVM has many more uses like cluster support, raid features, backup/recovery.
