To fully enable all Monyog functionalities you may also need to create one or more operating system users for specific purposes.
SSH tunneling: Monyog can send and receive encrypted authentication information as well as monitoring data from MySQL using SSH tunneling. Also, it will often be possible to connect to MySQL with SSH tunneling even if the MySQL port (normally 3306) is blocked by a firewall or if users are not allowed to connect from remote hosts. An operating system user is required so that Monyog SSH client functionalities can use this user to connect to the SSHD daemon on the server.
System information (currently available for Linux servers): For retrieving system information you will further need an Operating System user. The user must be a 'shell' user (it must be possible for this user to issue system commands). This user is specified for the SSH-based connection to the host.
This user must have read-access to the Linux '/proc' folder. Normally, this is always the case for Linux users. Also to retrieve memory related information this user must have read access to the .pid files created by the MySQL server. An easy way to ensure this is to add the user to the 'mysql' user group.
MySQL log information: For retrieving MySQL log information (when stored as files - not when stored as MySQL tables) read-access to the MySQL log files are also required.
You may of course (but need not) use the same operating system user for all the three above ways that Monyog connects to the OS.