A filesystem question
 

Below is the output when I run df -h:
Below is the output when I run ls -l at root home dir:
So can I assume /tmp, or /etc, or /lib64 are using the storgae that is 83% full? How to decide which sub directory under / will have its own file system? like, why /var has its own file system? Is it true that one partition will hold one and only one file system?

Thanks!

no, they are not using that, as the clearly have their own partition. This is decided by you or the installer. /var gets filled with logs and such, so you keep it seperate to, amongst other reasons, stop logs making your main disks run out of space. A partition can do loads of things. For example, sda4 on your disk will be an extended partition holding other logical partitions. an LVM partition can also hold an thousand separate filesystems if so desired.

Thanks. So if / is 83% full, what directories need to be looked at in order to clean some space?

I have listed all the partitions on the server above. If /tmp or /etc is not using the partition that is at 83%, then which partion it is using?

all the other directories that DON'T have their own partition

Personally I do this...

cd /
du -h --max-depth=1
[find large directory in output]
cd [that directory]
du -h --max-depth=1
[find large directory in output]
etc...

simple way to narrow things down.

HOWEVER. your / partition is *TINY* I wouldn't bother looking, that's about right. You need a bigger partition really.

Yes, you can. The output of df shows clearly that they don't have an associated partition, so they are using the / partition. I don't know why acid_kewpie comes to a different conclusion.

Yes.

Thanks a lot for the clarification!