Extend LVM without partition table
This Blog is continuation of my previous blog Create LVM without partition table.
In this scenario, we will extend the size of disk on VM instead of adding new disk.
Login to the VM and check if the increased size is visible. we can do this by rescanning the block device as shown below,
#echo 1 > /sys/class/scsi_device/2:0:1:0/device/rescan --> where 2:0:1:0 is the scsi interface of the device connected this can be identified using the lun number we have extended from vm portal and matching with lsscsi output.
#echo 1 > /sys/class/block/sdb/device/rescan --> Where sdb is the block device.
Now we will be able to see the new increased size for the disk using fdisk -l /dev/sdb or lsblk command.
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| 1.1 Disk Rescan |
Next we can resize the PV since we have not used or created a partition table.
Command to resize as below,
#pvresize /dev/sdb
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| 1.2 Resize PV |
Once we resize the PV, we can see the changes using pvs or pvdisplay command,
VG will be reflecting the free space available automatically we do not have to extend anything as we are using the same PV instead of new PV.
We can see the VG status using vgs or vgdisplay.
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| 1.3 vgs output |
Lets proceed with resize of LV directly using below command,
#lvresize -l +100%FREE lv_name
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| 1.4 LV resize |
Now we can see the lv has been resized with lvs or lvdisplay command.
Now the LV has required space, filesystem can be grown using below command,
#xfs_growfs /mount_point_name
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| 1.5 Resize Filesystem |
Once the filesystem is extended, we can see the change using df -h and its usable now.
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| 1.6 Resized mount |
We have increased the disk space without downtime and partition table.
Caution: When we use a partitionless LVM, we also need to be careful at later point in time when we add more disk, where our old disk used as LVM may also show as no partition in fdisk or parted commands. So, its recommended to use pvdisplay or pvs command validate and confirm its usage.
