apache2 is the Apache HyperText Transfer Protocol (HTTP) server program. It is designed to be run as a standalone daemon process. When used like this it will create a pool of child processes or threads to handle requests.
In general, apache2 should not be invoked directly, but rather should be invoked via /etc/init.d/apache2.
Set the initial value for the ServerRoot directive to serverroot. This can be overridden by the ServerRoot directive in the configuration file.
-f config
Uses the directives in the file config on startup. If config does not begin with a /, then it is taken to be a path relative to the ServerRoot. The default is /etc/apache2/apache2.conf.
-k start|restart|graceful|stop|graceful-stop
Signals apache2 to start, restart, or stop. See Stopping Apache for more information.
-C directive
Process the configuration directive before reading config files.
-c directive
Process the configuration directive after reading config files.
-D parameter
Sets a configuration parameter which can be used with <IfDefine> sections in the configuration files to conditionally skip or process commands at server startup and restart.
-e level
Sets the LogLevel to level during server startup. This is useful for temporarily increasing the verbosity of the error messages to find problems during startup.
-E file
Send error messages during server startup to file.
-R directory
When the server is compiled using the SHARED_CORE rule, this specifies the directory for the shared object files.
-h
Output a short summary of available command line options.
-l
Output a list of modules compiled into the server. This will not list dynamically loaded modules included using the LoadModule directive.
-L
Output a list of directives together with expected arguments and places where the directive is valid.
-M
Dump a list of loaded Static and Shared Modules.
-S
Show the settings as parsed from the config file (currently only shows the virtualhost settings).
-t
Run syntax tests for configuration files only. The program immediately exits after these syntax parsing tests with either a return code of 0 (Syntax OK) or return code not equal to 0 (Syntax Error). If -D DUMP_VHOSTS is also set, details of the virtual host configuration will be printed. If -D DUMP_MODULES is set, all loaded modules will be printed.
-v
Print the version of apache2, and then exit.
-V
Print the version and build parameters of apache2, and then exit.
-X
Run apache2 in debug mode. Only one worker will be started and the server will not detach from the console.
