Sentinel Agents

A Sentinel Agent is a small process that can start and stop Apama correlators and IAF adapters on the host where it is running. EMM starts and stops components on a particular host in a platform independent way by interacting with the Sentinel Agent running on that host. Therefore a Sentinel Agent must be running on any machine where you intend to manipulate Apama components using EMM.

If you checked the sentinel agent check box during the Apama installation process, sentinel agent is automatically installed with startup type =automatic.

By starting the Windows Service with the apama_services command apama_services -start -s sentinel. The service can be stopped with apama_services -stop -s sentinel. If the service was not added during installation it can be added with apama_services -add -s sentinel.

By starting the Sentinel Agent executable manually but not as a Windows Service. This can be done either from an Apama command prompt or command shell where you have run apama_env.bat to set the necessary Apama environment variables. Run sentinel_agent.exe and pass command line arguments to it.

By adding it as a service (daemon) through the installer. In this case the Sentinel Agent will automatically start up when the machine boots.

By starting the service with the apama_services command apama_services -start -s sentinel. The service can be stopped with apama_services -stop -s sentinel. If the service was not added during installation it can be added with apama_services -add -s sentinel.

By starting the Sentinel Agent either from a script or command shell where you have sourced apama_env. Run sentinel_agent and pass command line arguments to it.

Note: Any information written to stdout or stderr by components started with a Sentinel Agent will be logged in the Agent's log directory in files called <component-type>-<PID>-std{out,err}.log on UNIX and <component-type>-<num>-std{out,err}.log on Windows, where <PID> = Process Id and <num> is an integer number. Valid component types are correlator and adapter. The stdout / stderr logs will be deleted by Sentinel when the relevant component is stopped if they are empty (which should normally be the case).