每日一个linux命令21-df

1. 命令解析

命令用途：
查看磁盘使用及剩余空间情况

命令格式：

df [OPTION]... [FILE]...

命令参数：

-a, --all include dummy file systems
-B, --block-size=SIZE scale sizes by SIZE before printing them; e.g.,
'-BM' prints sizes in units of 1,048,576 bytes;
see SIZE format below
--direct show statistics for a file instead of mount point
--total produce a grand total
-h, --human-readable print sizes in human readable format (e.g., 1K 234M 2G)
-H, --si likewise, but use powers of 1000 not 1024
-i, --inodes list inode information instead of block usage
-k like --block-size=1K
-l, --local limit listing to local file systems
--no-sync do not invoke sync before getting usage info (default)
--output[=FIELD_LIST] use the output format defined by FIELD_LIST,
or print all fields if FIELD_LIST is omitted.
-P, --portability use the POSIX output format
--sync invoke sync before getting usage info
-t, --type=TYPE limit listing to file systems of type TYPE
-T, --print-type print file system type
-x, --exclude-type=TYPE limit listing to file systems not of type TYPE

2. 示例

2.1 查看信息

[root@test test]# df 
Filesystem     1K-blocks    Used Available Use% Mounted on
/dev/vda1       25670884 2503564  21840268  11% /
devtmpfs         1934228       0   1934228   0% /dev
tmpfs            1939484       0   1939484   0% /dev/shm
tmpfs            1939484  210684   1728800  11% /run
tmpfs            1939484       0   1939484   0% /sys/fs/cgroup
/dev/vdc1      103079868   61044  97759632   1% /data

2.2 指定单位 -B

[root@test test]# df -B K
Filesystem      1K-blocks     Used Available Use% Mounted on
/dev/vda1       25670884K 2503548K 21840284K  11% /
devtmpfs         1934228K       0K  1934228K   0% /dev
tmpfs            1939484K       0K  1939484K   0% /dev/shm
tmpfs            1939484K  210684K  1728800K  11% /run
tmpfs            1939484K       0K  1939484K   0% /sys/fs/cgroup
/dev/vdc1      103079868K   61044K 97759632K   1% /data
[root@test test]# df -B M
Filesystem     1M-blocks  Used Available Use% Mounted on
/dev/vda1         25070M 2445M    21329M  11% /
devtmpfs           1889M    0M     1889M   0% /dev
tmpfs              1895M    0M     1895M   0% /dev/shm
tmpfs              1895M  206M     1689M  11% /run
tmpfs              1895M    0M     1895M   0% /sys/fs/cgroup
/dev/vdc1        100664M   60M    95469M   1% /data
[root@test test]# df -B G
Filesystem     1G-blocks  Used Available Use% Mounted on
/dev/vda1            25G    3G       21G  11% /
devtmpfs              2G    0G        2G   0% /dev
tmpfs                 2G    0G        2G   0% /dev/shm
tmpfs                 2G    1G        2G  11% /run
tmpfs                 2G    0G        2G   0% /sys/fs/cgroup
/dev/vdc1            99G    1G       94G   1% /data

2.3 以友好的方式展示 -h

[root@test test]# df -h
Filesystem      Size  Used Avail Use% Mounted on
/dev/vda1        25G  2.4G   21G  11% /
devtmpfs        1.9G     0  1.9G   0% /dev
tmpfs           1.9G     0  1.9G   0% /dev/shm
tmpfs           1.9G  206M  1.7G  11% /run
tmpfs           1.9G     0  1.9G   0% /sys/fs/cgroup
/dev/vdc1        99G   60M   94G   1% /data

2.4 显示inode信息 -i

[root@test test]# df -ih
Filesystem     Inodes IUsed IFree IUse% Mounted on
/dev/vda1        1.6M   72K  1.5M    5% /
devtmpfs         473K   328  472K    1% /dev
tmpfs            474K     1  474K    1% /dev/shm
tmpfs            474K   356  474K    1% /run
tmpfs            474K    13  474K    1% /sys/fs/cgroup
/dev/vdc1        6.3M    11  6.3M    1% /data

2.5 显示文件系统类型 -T

[root@test test]# df -T
Filesystem     Type     1K-blocks    Used Available Use% Mounted on
/dev/vda1      ext4      25670884 2503600  21840232  11% /
devtmpfs       devtmpfs   1934228       0   1934228   0% /dev
tmpfs          tmpfs      1939484       0   1939484   0% /dev/shm
tmpfs          tmpfs      1939484  210684   1728800  11% /run
tmpfs          tmpfs      1939484       0   1939484   0% /sys/fs/cgro

2.6 显示特定文件类型 -t

[root@test test]# df -t ext4
Filesystem     1K-blocks    Used Available Use% Mounted on
/dev/vda1       25670884 2503624  21840208  11% /
/dev/vdc1      103079868   61044  97759632   1% /data

2.7 不显示特定文件类型 -x

[root@test test]# df -x ext4
Filesystem     1K-blocks   Used Available Use% Mounted on
devtmpfs         1934228      0   1934228   0% /dev
tmpfs            1939484      0   1939484   0% /dev/shm
tmpfs            1939484 210684   1728800  11% /run
tmpfs            1939484      0   1939484   0% /sys/fs/cgroup