Single User Mode (sometimes known as Maintenance Mode) is a mode in Unix-like operating systems such as Linux operate, where a handful of services are started at system boot for basic functionality to enable a single superuser perform certain critical tasks.

What does single user mode do?

Single-user mode is a mode in which a multiuser computer operating system boots into a single superuser. It is mainly used for maintenance of multi-user environments such as network servers. Some tasks may require exclusive access to shared resources, for example running fsck on a network share.

How do I put Linux into single user mode?

In the GRUB menu, find the kernel line starting with linux /boot/ and add init=/bin/bash at the end of the line. Press CTRL+X or F10 to save the changes and boot the server into single user mode. Once booted the server will boot into root prompt.