The largest area in the Application Director view shows the “standard output / standard error” output text for the selected station (Figure 9).
Depending on the status of the station selected, the standard output text is one of the following:
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If a running station, output updates in real time. As more text is written by the station, it is appended to the bottom of the output area.
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If the station is not running, output text is from the most recent execution of that station.
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If no station is selected, output text area is blank.
Use the Windows copy shortcut (Ctrl-C) to copy output text to the clipboard.
As needed, use scroll bars to view all text, and use the right-side output control buttons. For more details, see Output control buttons.
The following sections provide more details related to a station’s standard output:
Station output messages can include errors and warnings that let you why something is not working, as well as simple informational messages about events as they occur. If needed, you can also change the “level” of station output—see station log levels.
The general format of a station output message is:
TYPE [timestamp] [station_process] message_text
For example:
MESSAGE [13:53:08 08-Mar-12][fox] FOX server started on port [1911]
Message types seen in station output include the following, by leading text descriptor
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MESSAGE
Typically comprise most default station output messages. Usually, each message lets you know some process milestone was started or reached, such as a service or the station itself.
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WARNING
Informs you of a potential problem, such as inability to open a specific port. Typically, warnings do not keep a station from starting.
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ERROR
Informs you of a problem that might keep the station from starting. Or, if it can start, an error that prevents some function of the station from operating correctly.
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TRACE
A verbose debug-level message that may be generated upon every process transaction. Useful only in advanced debugging mode. You see these for station processes only if you have set the log level at “
Trace”.
In addition to the “typed” output messages described above, occasionally you may see a string of “java exception” text in the a station’s output. This indicates an unforeseen station execution issue, which can range from a licensing problem, a misconfiguration, or some other unexpected problem. If an unexplained exception reoccurs, copy the exception text and report the problem to Systems Engineering.
A running station is a combination of many ongoing processes. Using the station’s spy “logSetup” page (Figure 10), you can change the “log level” of the station processes of interest in order to “tune” station output.
To get to a running station’s logSetup page in Workbench, double-click the station in the Nav tree for its Station Summary view. From there, double-click Spy, then click logSetup.
By default, all station processes have a “Message” log level (level selection denoted by [X]). To change the level of any listed process, click in the desired level column.
Level selection columns are ordered left-to-right in decreasing order of message volume, as follows:
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Trace
Returns all message activity (verbose). This includes all transactional messages, which may result in too many messages to be useful. Be careful using Trace!
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Message
(Default) Returns informational “MESSAGE”s, plus all “ERROR” and “WARNING” types.
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Warning
Returns only “ERROR” and “WARNING” type messages (no informational “MESSAGE”s).
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Error
Returns only “ERROR” type messages (no “WARNING” or informational “MESSAGE”s).
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None
No messages are returned to the station’s output.
Increasing station output by assigning trace levels consumes extra station resources and exacts a performance penalty! After
troubleshooting, return log levels to default values.
If a station is configured with the LogHistoryService (under its Services container), it maintains a buffered history (“LogHistory”)
of some of the messages seen in the station’s standard output. In the LogHistoryService’s configuration, you specify its log level,
meaning the minimum message type (from station output) to log. By default, the log level (property “Minimum Severity”) is
Error. You may wish to change this to Warning.
This is mentioned because when looking at a station’s output, you are usually troubleshooting. As part of troubleshooting, you should always check the station’s histories for LogHistory. It should contain recently recorded station errors and (if configured) warnings. This information may help when evaluating “live” output from the station.