Daemon Processes
What are Daemon Processes?
Daemons are processes that are constantly or continuously running in the background, rather than being interactively controlled by a user through CUI (Character User Interface) or GUI (Graphic User Interface). Daemon processes are usually launched when the OS starts, and continue to run until the OS shuts down. The first Daemon process that starts when the OS starts is called systemd
, which will be explained in the next section.
Examples of Daemon Processes
Network programs, security programs, time managers, log journals and other processes running on the OS in the background are all daemon processes. Usually, daemons have a name that ends with -d
. For example, sshd
is a daemon for ssh connection, firewalld
is a daemon for a firewall management tool for Linux OS. httpd
is a daemon used for Apache HTTP Server.