Filesystem Usage

Linux System Administrators Guide:
Prev | Chapter 7. System Monitoring | Next

# 7.2. Filesystem Usage

Many reports are currently talking about how cheap storage has gotten, but if you're like most of us it isn't cheap enough. Most of us have a limited amount of space, and need to be able to monitor it and control how it's used.

## 7.2.1. The df command

The df is the simplest tool available to view disk usage. Simply type in df and you'll be shown disk usage for all your mounted filesystems in 1K blocks

    user@server:~> df
    Filesystem           1K-blocks      Used Available Use% Mounted on
    /dev/hda3              5242904    759692   4483212  15% /
    tmpfs                   127876         8    127868   1% /dev/shm
    /dev/hda1               127351     33047     87729  28% /boot
    /dev/hda9             10485816     33508  10452308   1% /home
    /dev/hda8              5242904    932468   4310436  18% /srv
    /dev/hda7              3145816     32964   3112852   2% /tmp
    /dev/hda5              5160416    474336   4423928  10% /usr
    /dev/hda6              3145816    412132   2733684  14% /var

You can also use the -h to see the output in "human-readable" format. This will be in K, Megs, or Gigs depending on the size of the filesystem. Alternately, you can also use the -B to specify block size.

In addition to space usage, you could use the -i option to view the number of used and available inodes.

    user@server:~> df -i
    Filesystem            Inodes   IUsed   IFree IUse% Mounted on
    /dev/hda3                  0       0       0    -  /
    tmpfs                  31969       5   31964    1% /dev/shm
    /dev/hda1              32912      47   32865    1% /boot
    /dev/hda9                  0       0       0    -  /home
    /dev/hda8                  0       0       0    -  /srv
    /dev/hda7                  0       0       0    -  /tmp
    /dev/hda5             656640   26651  629989    5% /usr
    /dev/hda6                  0       0       0    -  /var

## 7.2.2. The du command

Now that you know how much space has been used on a filesystem how can you find out where that data is? To view usage by a directory or file you can use du. Unless you specify a filename du will act recursively. For example:

    user@server:~> du file.txt
    1300    file.txt

Or like the df I can use the -h and get the same output in "human-readable" form.

    user@server:~> du -h file.txt
    1.3M     file.txt

Unless you specify a filename du will act recursively.

    user@server:~> du -h /usr/local
    4.0K    /usr/local/games
    16K     /usr/local/include/nessus/net
    180K    /usr/local/include/nessus
    208K    /usr/local/include
    62M     /usr/local/lib/nessus/plugins/.desc
    97M     /usr/local/lib/nessus/plugins
    164K    /usr/local/lib/nessus/plugins_factory
    97M     /usr/local/lib/nessus
    12K     /usr/local/lib/pkgconfig
    2.7M    /usr/local/lib/ladspa
    104M    /usr/local/lib
    112K    /usr/local/man/man1
    4.0K    /usr/local/man/man2
    4.0K    /usr/local/man/man3
    4.0K    /usr/local/man/man4
    16K     /usr/local/man/man5
    4.0K    /usr/local/man/man

If you just want a summary of that directory you can use the -s option.

    user@server:~> du -hs /usr/local
    210M    /usr/local

## 7.2.3. Quotas

For more information about quotas you can read The Quota HOWTO .

Prev | Home | Next
System Resources | Up | Monitoring Users