Options restrict in one filesystem

There are quite number of tasks may want to be executed in one filesystem, this is important during troubleshooting, especially for root directory (/).

find

Restrict find command only looking entries within one filesystem, use option -xdev

find /usr -xdev ...

du

Restrict du command only calculate for one filesystem, use option -x

du -cshx /

tar

Restrict tar command only archive files in one filesystem, use option --one-file-system

tar --one-file-system -czvf /tmp/root.tgz /