Your linux server setup is completed and server is up and running seamlessly. You have found and installed all the tools required to run your application servers. Only maintenance required is regular checkup for updates.
Have you ever bothered about checking the Disk Space of your linux server. Disk Space is a very big headache for the server which have more storage and frequent write operations.
Every application that is running will have logging enabled and mostly stored in the same machine where application is running. This is one of the example which will consume Disk Space. Apart from logs, there will be few other operations like creating automatic documents, storing files in the server and so on. All these will consume Disk Space.
You will get so many GUI tools out there in the internet for checking DiskSpace like QDirStat, GdMap, xdiskusage and Gnome’s Disk Usage Analyzer. However, Linux provides a strong built-in utility called `df`. `df` stands for `disk filesystem`. It is used to get the full summary of the Available and Used disk space on Linux Servers.
Mostly used df command is
-h switch stands for human readable format of the Sizes of files
-k switch stands for human readable format of the Sizes of files in KB format
-T switch stands for Type of the file system. -T will print the file system Type on the output.
-x switch is used to exclude specific file system
- df -x ext3
- df -x tmpfs
Complete usage of df command is explained here
Usage: df [OPTION]… [FILE]…
Show information about the file system on which each FILE resides,
or all file systems by default.
Mandatory arguments to long options are mandatory for short options too.
-a, –all include pseudo, duplicate, inaccessible 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
-h, –human-readable print sizes in powers of 1024 (e.g., 1023M)
-H, –si print sizes in powers of 1000 (e.g., 1.1G)
-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
–total elide all entries insignificant to available space,
and produce a grand total
-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
–help display this help and exit
–version output version information and exit
Display values are in units of the first available SIZE from –block-size,
and the DF_BLOCK_SIZE, BLOCK_SIZE and BLOCKSIZE environment variables.
Otherwise, units default to 1024 bytes (or 512 if POSIXLY_CORRECT is set).
The SIZE argument is an integer and optional unit (example: 10K is 10*1024).
Units are K,M,G,T,P,E,Z,Y (powers of 1024) or KB,MB,… (powers of 1000).
FIELD_LIST is a comma-separated list of columns to be included. Valid
field names are: ‘source’, ‘fstype’, ‘itotal’, ‘iused’, ‘iavail’, ‘ipcent’,
‘size’, ‘used’, ‘avail’, ‘pcent’, ‘file’ and ‘target’ (see info page).