linuxexpert-practice-labs/labs/linux-plus/1-1-2-filesystem-hierarchy

Linux+ 1.1.2: The filesystem hierarchy

A tour of the directory tree: links into /usr, what uses space under /var, real and virtual filesystems, and which package owns a file.

Before you start

The lab sets nothing up. Each task asks for a finding: write it to the file in /root/lab-answers/ that the task names.

Tasks

1. Look at /bin, /sbin, /lib and /tmp with ls -ld. Write the ones that are symbolic links, one per line, to /root/lab-answers/1.
2. Find the directory under /var that uses the most space, and write its full path (such as /var/spool) to /root/lab-answers/2.
3. List the mount points of the real filesystems (not virtual ones such as /proc), one per line, in /root/lab-answers/3.
4. Ask the package manager which package owns /usr/bin/ls, and write the package name to /root/lab-answers/4. Then create /etc/mynote and see what it says about that file; remove /etc/mynote again.

Hints

• ls -ld /bin /sbin /lib /tmp: links start with l. Note the t at the end of /tmp's permissions: the sticky bit.
• du -sh /var/* 2>/dev/null | sort -h | tail.
• findmnt --real, df -hT; findmnt --real -rn -o TARGET prints just the mount points.
• rpm -qf on the RHEL family, dpkg -S on Debian and Ubuntu.