Red Hat Summit Red Hat SummitSupportConsoleDevelopersStart a trialContact

2.3. Unmounting a File System

To detach a previously mounted file system, use either of the following variants of the umount command:
Copy to Clipboard Toggle word wrap 
umount directory
umount device
Note that unless you are logged in as root, you must have permissions to unmount the file system (see Section 2.2.2, “Specifying the Mount Options”). See Example 2.9, “Unmounting a CD” for an example usage.

Important

When a file system is in use (for example, when a process is reading a file on this file system), running the umount command will fail with an error. To determine which processes are accessing the file system, use the fuser command in the following form:
Copy to Clipboard Toggle word wrap 
fuser -m directory
For example, to list the processes that are accessing a file system mounted to the /media/cdrom/ directory, type:
Copy to Clipboard Toggle word wrap 
~]$ fuser -m /media/cdrom
/media/cdrom:         1793  2013  2022  2435 10532c 10672c

Example 2.9. Unmounting a CD

To unmount a CD that was previously mounted to the /media/cdrom/ directory, type the following at a shell prompt:
Copy to Clipboard Toggle word wrap 
~]$ umount /media/cdrom
Back to top
Red Hat logoGithubredditYoutubeTwitter

Learn

Try, buy, & sell

Communities

About Red Hat Documentation

We help Red Hat users innovate and achieve their goals with our products and services with content they can trust. Explore our recent updates.

Making open source more inclusive

Red Hat is committed to replacing problematic language in our code, documentation, and web properties. For more details, see the Red Hat Blog.

About Red Hat

We deliver hardened solutions that make it easier for enterprises to work across platforms and environments, from the core datacenter to the network edge.

Theme

© 2025 Red Hat, Inc.