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In the book I am reading, the output of df command is shown like this:

Filesystem 1K-blocks     Used Available Use% Mounted on
/dev/sda2   15115452  5012392   9949716  34% /
/dev/sda5   59631908 26545424  30008432  47% /home
/dev/sda1     147764    17370    122765  13% /boot
tmpfs         256856        0    256856   0% /dev/shm

But when I run the same command (whilst passing the -h parameter) on my Ubuntu server (VirtualBox VM), the output is like this:

Filesystem          Size  Used Avail Use% Mounted on
/dev/mapper/a-root  4.2G  1.1G  3.0G  26% /
udev                741M  4.0K  741M   1% /dev
tmpfs               300M  268K  300M   1% /run
none                5.0M     0  5.0M   0% /run/lock
none                750M     0  750M   0% /run/shm
/dev/sda1           228M   27M  190M  13% /boot

What I want to know is, why is /home directory missing? And what exactly is the criteria that the listed directories fulfill? (I mean, / is listed, but not /home. But /run is there, and also /run/lock and /run/shm. Why the bias?)

its_me
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2 Answers2

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df shows you the utilization and free space on filesystems. Obviously, on your machine, /home is not a filesystem but a mere directory.

MelBurslan
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  • So, in simple terms, `/home` isn't listed because it isn't on a different partition or device; and in my case, it's in the `/` (root) file system itself, right? – its_me Apr 12 '13 at 17:51
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    yes, very much so... But if you are using LVM (logical volume manager) every filesystem doesn't have to reside on a different partition. One partition can be made looking like multiple partitions. Hence the name, Logical. – MelBurslan Apr 12 '13 at 17:55
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Furthermore, you can type mount to check currently mounted filesystems. Whatever filesystems df displays, they should be on that list, too. If you want to check how much of the disk space does your /home directory use, you can do du -sh /home (if that's what you originally intended).

TNW
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