Scenarios

When the capacity of a logical volume becomes insufficient, you can expand its capacity. This topic shows how to add 4 GB space for a 15 GB logical volume, which cannot meet requirements.

During the capacity expansion, ensure that the volume group where the to-be-expanded logical volume belongs has sufficient available space. If the volume group's available space is also insufficient, expand the capacity of the volume group according to Adding an EVS Disk to Expand the Capacity of a Volume Group.

Procedure

1. Log in to the ECS as user root.
2. Run the following command to expand the capacity of the logical volume:

   lvextend -L +Additional capacity Logical volume path

   Parameter descriptions:

   • Additional capacity: Specify a value smaller than the volume group's available space, either in MB or GB.
   • Logical volume path: Specify the path of the to-be-expanded logical volume.

   For example, run the following command:

   lvextend -L +4GB /dev/vgdata/lvdata1

   Information similar to the following is displayed:

   [root@ecs-lvmtest ~]# lvextend -L +4GB /dev/vgdata/lvdata1
     Size of logical volume vgdata/lvdata1 changed from 15.00 GiB (3840 extents) to 19.00 GiB (4864 extents).
     Logical volume vgdata/lvdata1 successfully resized.

   This step expands only the capacity of the logical volume. You also need to expand the size of the file system on this volume.

3. Run the following command to expand the size of the file system:

   resize2fs Logical volume path

   For example, run the following command:

   resize2fs /dev/vgdata/lvdata1

   Information similar to the following is displayed:

   [root@ecs-lvmtest ~]# resize2fs /dev/vgdata/lvdata1
   resize2fs 1.42.9 (28-Dec-2013)
   Filesystem at /dev/vgdata/lvdata1 is mounted on /Data1; on-line resizing required
   old_desc_blocks = 4, new_desc_blocks = 28
   The filesystem on /dev/vgdata/lvdata1 is now 3657728 blocks long.

4. Run the following command to check whether the file system size increases:

   df -h

   Information similar to the following is displayed:

   [root@ecs-lvmtest ~]# df -h
   Filesystem                  Size  Used Avail Use% Mounted on
   /dev/vda2                    39G  1.5G   35G   5% /
   devtmpfs                    487M     0  487M   0% /dev
   tmpfs                       496M     0  496M   0% /dev/shm
   tmpfs                       496M  6.7M  490M   2% /run
   tmpfs                       496M     0  496M   0% /sys/fs/cgroup
   /dev/vda1                   976M  131M  779M  15% /boot
   tmpfs                       100M     0  100M   0% /run/user/0
   /dev/mapper/vgdata-lvdata1   19G   44M   18G   1% /Data1

   In the command output, the size of file system /dev/mapper/vgdata-lvdata1 increases by 4 GB.