[root@localhost ~]# mkfs.ext4 /dev/xvda

xvda xvda1 xvda2 xvda3

[root@localhost ~]# mkfs.ext4 /dev/xvda3

mke2fs 1.42.9 (28-Dec-2013)

Filesystem label=

OS type: Linux

Block size=4096 (log=2)

Fragment size=4096 (log=2)

Stride=0 blocks, Stripe width=0 blocks

44040192 inodes, 176160768 blocks

8808038 blocks (5.00%) reserved for the super user

First data block=0

Maximum filesystem blocks=2323644416

5376 block groups

32768 blocks per group, 32768 fragments per group

8192 inodes per group

Superblock backups stored on blocks:

32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,

4096000, 7962624, 11239424, 20480000, 23887872, 71663616, 78675968,

102400000

Allocating group tables: done

Writing inode tables: done

Creating journal (32768 blocks): done

Writing superblocks and filesystem accounting information: done

[root@localhost ~]# mkdir /haha

[root@localhost ~]# mount /dev/xvda3 /haha

[root@localhost ~]# df -h

Filesystem Size Used Avail Use% Mounted on

/dev/mapper/centos-root 50G 1.3G 49G 3% /

devtmpfs 3.9G 0 3.9G 0% /dev

tmpfs 3.7G 0 3.7G 0% /dev/shm

tmpfs 3.7G 8.4M 3.7G 1% /run

tmpfs 3.7G 0 3.7G 0% /sys/fs/cgroup

/dev/mapper/centos-home 74G 33M 74G 1% /home

/dev/xvda1 497M 96M 402M 20% /boot

/dev/xvda3 662G 73M 628G 1% /haha