# Agent Matrix
This article discusses how FGSMS agents function, particularly how they collect statistics and availability information and report that data back to the server.
FGSMS includes a number of different agents that serve different purposes.
| Agent | Type | Runs at | Status | Metrics | Notes |
|---|---|---|---|---|---|
| Generic JAXWS | Web Service | JAXWS Handler | Bueller | Sent on demand | Covers Axis 2.0, SunRI, Metro and CXF |
| Apache CXF | Web Service | Interceptor | Bueller | Sent on demand | Covers JAXWS and JAXRS with Apache CXF |
| Jboss ESB | Web Service | Embedded | Bueller | Sent on demand | Implements the proxy method of monitoring |
| Java Servlets | Web Service | Embedded | Bueller | Sent on demand | v2.5 or newer |
| .NET WCF and ASP.NET | Web Service | Embedded or OS wide | Bueller | Sent on demand | Covers IIS and self hosted services and clients via .config file. Can be applied globally via Machine.config applies to all |
| Apache Axis 1.x | Web Service | Embedded | Bueller | Sent on demand | Covers Apache Axis 1.3-1.4 based services |
| OS Agent | Operating System | Standalone Process | Self reporting, 30 sec interval | Self reporting, 30 sec interval, Covers processes and system level metrics | |
| HornetQ via JMS | Broker | FGSMS server | Self reporting, 30 sec interval | Self reporting, 30 sec interval | |
| Apache Qpid via JMS | Broker | FGSMS server | Self reporting, 30 sec interval | Self reporting, 30 sec interval | |
| Apache Qpid Python | Broker | Standalone | Self reporting, 30 sec interval | Self reporting, 30 sec interval | |
| Apache ServiceMix via JMS | Broker | FGSMS server | Self reporting, 30 sec interval | Self reporting, 30 sec interval | |
| Bueller | Status | FGSMS server | Self reporting, 30 sec interval | Self reporting, 30 sec interval | Attempts an HTTP connection to the web service/server |
Transmission rates for non-web service agents are centrally configured via the FGSMS user interface. See Global Policies and General Settings in the User Guide
(*) notates that this information isn’t always available depending on the framework, agent type, or operating configuration.
FGSMS comes with an Operating System Agent that uses the SIGARS API. It provides monitoring on a variety of different platforms. The following data points can be recorded:
OS Wide
Process specific
The OS Agent covers nearly all Windows and Linux/Unix flavored operating systems (except Android). For processes, FGSMS will aggregate multiple instances of a specific process together.
Message brokers are generally publish and subscribe servers that collect their own statistics in their own way and generally expose them as either JMX end points or via some kind of command line interface.
Right now, there’s only one status only agent called Bueller. Named after Ferris Bueller’s Day Off, Bueller periodically ‘pings’ each endpoint by essentially calling executing a HTTP GET request to the service URL. FGSMS’s Bueller function was originally designed to hit XML SOAP services is to automatically appends a ?wsdl to the request URL.
Bueller can also support scenarios where authentication is required, including most HTTP authentication types, including NTLM and PKI/X509 certificate authentication.
Via TCP/HTTP/XML/SOAP messages. Agents only communicate with the Policy and Configuration Service (PCS), the Data Collector Service (DCS), and the Status Service (SS). Authentication can be username/password or PKI authentication.
Most agents have built in support load balancing/failover for communicating with FGSMS’s server and if enabled, they will support dynamic discovery of FGSMS’s server endpoints via a variety of mechanisms.
In the event an agent cannot access the FGSMS endpoints, it can be configured to perform a number of actions. - Keep the content in memory and continue to retrying - Drop the content - Store it to disk, when connectivity is reestablished, content on disk will be enqueued for transmission.