The more common command to check mounted file systems on linux is the mount command which is used to not only list mounted devices, but also mount and unmount them as and when needed. Here is another nifty command called findmnt, that can be used to take a quick look at what is mounted where and with what options.
The findmnt command comes from the packages util-linux which is installed by default on most distros like Ubuntu, Fedora, Debian
$ aptitude search util-linux
i util-linux - Miscellaneous system utilities
$ yum info util-linux
1. List the file systems
Running findmnt without any options would simply list out all the mounted file systems in a tree style layout.
2. Output in list format
The output can be formatted as a plain list, instead of the default tree style, using the l option making it convenient to read.
$ findmnt -l
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8 examples of findmnt command to check mounted file systems on Linux