[CentOS] Unable to find the used space

On Mon, 29 Jun 2020 15:21:12 +0530
Sachchidanand Upadhyay via CentOS <centos at centos.org> wrote:

> Hi,
> 
>  While checking with df -h, it's showing the used space is 94% on
> root (/). If checked with du -sh, it's not showing the used space.
> 
>   # df -h
> Filesystem Size Used Avail Use% Mounted on
> devtmpfs 7.8G 0 7.8G 0% /dev
> tmpfs 7.8G 0 7.8G 0% /dev/shm
> tmpfs 7.8G 857M 7.0G 11% /run
> tmpfs 7.8G 0 7.8G 0% /sys/fs/cgroup
> /dev/mapper/centos-root 50G 47G 3.4G 94% /
> /dev/mapper/centos-home 241G 47G 195G 20% /var/log
> /dev/sda1 1014M 189M 826M 19% /boot
> tmpfs 1.6G 0 1.6G 0% /run/user/0
> tmpfs 1.6G 0 1.6G 0% /run/user/1002

As an addition to what others have already said. You'll also miss
things "hidden under mounts". That is, if you had 5G in /var/log on the
root file system and then mounted a different device on /var/log, then
that 5G would still be there but invisible.

Also, /dev/mapper/centos-home, HOME?!, on /var/log?

/Peter