How Do I Extend the File System of an Unpartitioned Data Disk in Linux?

Scenarios

If no partition but only a file system is created on a data disk, extend the file system according to the following operations:

Run the lsblk command. Information similar to the following is displayed:

[root@ecs-test ~]# lsblk
NAME     MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
vda      253:0    0   40G  0 disk
└─vda1 253:1    0   40G  0 part /
vdb      253:16   0   60G  0 disk /mnt/sdc

In the command output, no partition but only a file system is created on data disk /dev/vdb.

In the following example, CentOS 7.4 64bit is used as the sample OS, data disk /dev/vdb has 10 GB, no partition but only a file system is created on the disk, and additional 50 GB has been added to this data disk on the management console. The following steps show how to extend this 50 GB to the file system.

• Extending the EXT* File System
• Extending the XFS File System

The way you allocate additional space depends on the OS. This example is used for reference only. For the detailed operations and differences, see the corresponding OS documentations.

Extending the EXT* File System

1. Run the following command to extend the file system:

   resize2fs Disk name

   In this example, run the following command:

   resize2fs /dev/vdb

   Information similar to the following is displayed:

   [root@ecs-test ~]# resize2fs /dev/vdb
   resize2fs 1.42.9 (28-Dec-2013)
   Filesystem at /dev/vdb is mounted on /root/test; on-line resizing required
   old_desc_blocs = 2, old_desc_blocs = 8
   [17744.521535] EXT4-fs (vdb): resizing filesystem from 26214400 to 15728640 blocks
   [17744.904470] EXT4-fs (vdb): resized filesystem to 15728640
   The filesystem on /dev/vdb is now 15728640 blocks long.

2. Run the following command to view the result:

   df -TH

   Information similar to the following is displayed:

   [root@ecs-test ~]# df -TH
   Filesystem     Type      Size  Used Avail Use% Mounted on
   /dev/vda1      ext4       43G  1.9G   39G   5% /
   devtmpfs       devtmpfs  2.0G     0  2.0G   0% /dev
   tmpfs          tmpfs     2.0G     0  2.0G   0% /dev/shm
   tmpfs          tmpfs     2.0G  9.1M  2.0G   1% /run
   tmpfs          tmpfs     2.0G     0  2.0G   0% /sys/fs/cgroup
   tmpfs          tmpfs     398M     0  398M   0% /run/user/0
   /dev/vdb       ext4       64G   55M   61G   1% /mnt/sdc

Extending the XFS File System

1. Run the following command to extend the file system:

   xfs_growfs Disk name

   In this example, run the following command:

   xfs_growfs /dev/vdb

   Information similar to the following is displayed:

   [root@ecs-test ~]# xfs_growfs /dev/vdb 
   meta-data=/dev/vdb               isize=512     agcount=4, agsize=655360 blks
            =                       sectsz=512    attr=2, projid32bit=1
            =                       crc=1         finobt=0, spinodes=0
   data     =                       bsize=4096    blocks=2621440, imaxpct=25
            =                       sunit=0       swidth=0 blks
   naming   =version2               bsize=4096    ascii-ci=0 ftype=1
   log      =internal               bsize=4096    blocks=2560, version=2
            =                       sectsz=512    sunit=0 blks, lazy-count=1
   realtime =none                   extsz=4096    blocks=0, rtextents=0
   data blocks changed from 2621440 to 15728640.

2. Run the following command to view the result:

   df -TH

   Information similar to the following is displayed:

   [root@ecs-test ~]# df -TH
   Filesystem     Type      Size  Used Avail Use% Mounted on
   /dev/vda1      ext4       40G  2.3G   35G   7% /
   devtmpfs       devtmpfs  1.9G     0  1.9G   0% /dev
   tmpfs          tmpfs     1.9G     0  1.9G   0% /dev/shm
   tmpfs          tmpfs     1.9G  8.6M  1.9G   1% /run
   tmpfs          tmpfs     1.9G     0  1.9G   0% /sys/fs/cgroup
   tmpfs          tmpfs     379M     0  379M   0% /run/user/0
   /dev/vdb       xfs        60G   34M   60G   1% /mnt/sdc