Log message structure
The information contained in the log file messages has a consistent structure. Understanding this structure is critical for interpreting the information in the log files.
Loggable messages are generated by many subsystems of ArcGIS Server. Messages are generated as a result of server object manager (SOM) startup and administrative and user usage. Each message has a target that can be either the server or a service. Server-targeted messages log events associated with the core functionality of the SOM, while service messages log events associated with a specific service configuration and instances of that service configuration.
All log messages have these properties:
- time—The time at which the logged event occurred
- type—The level of detail of the message in relation to other messages (See Interpreting log files for descriptions of all the levels.)
- code—The result code associated with the message
- target—Either "Server" or the name of a service configuration associated with the message
- thread—The SOM process thread that generated the message
These additional properties may be included with the message:
- methodName—The method call on the service that resulted in the log message.
- machine—The server object container machine on which the event occurred. For example, the server may log an error that a server context for a particular service configuration could not be created on a particular machine. Only those messages that apply to statistics recorded for a specific machine will include a machine property.
- user—The user who submitted the request resulting in the log message. This property is useful when ArcGIS Server security is enabled.
- elapsed—The time it took for the event that is being logged to be complete. For example, the create server object event has an elapsed time to indicate the amount of time it took to create the service instance.
The log message is a human-readable description of the logged event that includes the process and thread IDs of the container processes where the service that generated the message is running and the server object container machine on which that process is running (if applicable). The message may contain any error description that comes from the service itself, such as an error indicating that it cannot write its output.
The following is an example of a typical log message. This log message indicates that an instance of the Yellowstone map service was created on the server object container machine padisha, and it took 2.443 seconds to create the service.
<Msg time='2009-10-31T14:36:05' type='INFO3' code='4004' target='Yellowstone.MapServer' machine='padisha' user='Fred' thread='2936' elapsed='2.443'> Server Object instance is successfully created on machine padisha. </MSG>
Message targets
The targets for the log messages can be either the server or a service. Messages associated with services have the name and type of the service as the target property. For example, the Yellowstone map service will appear as Yellowstone.MapServer.
There are two additional targets that will appear in the log that are internal service configurations. While the administrator does not manage these configurations directly, errors may still occur with them that need to be dealt with.
The internal services are SDM.ServerDirectoryManager and Engine.Engine. SDM.ServerDirectoryManager is the object that cleans files from the GIS server's server directories. An instance of SDM.ServerDirectoryManager is created when the SOM starts. Each time a directory is cleaned, this instance of SDM.ServerDirectoryManager does the cleaning for all server directories. Any errors it encounters are reported. Errors that are typically reported by SDM.ServerDirectoryManager include the inability to access a directory it needs to clean.
Each time a server directory is created or removed, SDM.ServerDirectoryManager is stopped and restarted.
The Engine.Engine service represents the empty server context configuration. When a client asks to create an empty context, the Engine.Engine configuration creates one for the client.