Semaphore application log files
- Last Updated: May 13, 2026
- 5 minute read
- Semaphore
- Documentation
This section describes the available logging facilities for the Semaphore applications. Log files can be used to help trace down issues and/or track activity occurring in the various Semaphore components.
Classification Server Logging
| Default Configuration File | /etc/opt/semaphore/CS/conf/config.xml (configuration format is originally based on the “log4cpp” logging mechanism) |
|---|---|
| Default Log Location | /var/opt/semaphore/CS/logs/ |
| Log Levels | **DEBUG - Most verbose logging INFO - Information logging messages NOTICE - Notification logging messages WARN - Warning messages (recommended setting for production use) ERROR - Error messages CRIT - Critical (error) messages ALERT - Alerting messages (not used) FATAL **- Fatal (error) messages |
| Log File Name | crt.log - Contains a log of all (successful) requests to CS (configured in the “crt_appender”, and “crt_audit” beans of the configuration file). runtime.log - Contains a log of all CS activity (configured in the “runtime_appender” bean of the configuration file). |
| Log File Format (crt.log) | Layout is configurable in the configuration file, default is as follows (CSV format): 0,<Finish time in yyyy-MM-dd HH:mm:ssZ“>,<Source IP Address>,<Operation>,<Time Taken>,<File Name>,<URL>,<Meta Original URL>,<Document Hash>,<Audit Tag>,<Scores> If error, then the format is as follows: <Error Number>,<Finish time in yyyy-MM-dd HH:mm:ssZ”>,<Source IP Address>,<Operation>,<Time Taken>,<File Name>,<URL>,<Meta Original URL>,<Audit Tag>,<Error Component>,<Error Message> |
| Log File Format (runtime.log) | <Request date in dd Mmm YYYY HH:mm:ss.sss> [<thread>] [component] : <Message> |
Note: For any classification server failures, the “failures” directory (set in the “failure_dir” setting, enabled by default) contains a file with the request and (if possible) another file containing the original document. Similarly you can configure classification server to save any successful requests (for debugging purposes) by un-commenting the “success_dir” settings from the default configuration file.
Document Analyzer (Studio Component) Logging
| Default Log Location | /var/opt/semaphore/da/logs/ |
|---|---|
| Log Levels | **TRACE - Most verbose logging DEBUG - Debugging log messages INFO - Information logging messages WARN - Warning messages (recommended setting for production use) ERROR **- Error messages only |
| Log File Name (Default) | DA.log (log file rotation based upon date) |
| Log File Format | YYYY-MM-DD HH:MM:SS.sss <Message Level> [<section>] <class section> - <Message text> |
Additional log files in “/var/opt/semaphore/da/logs” that may of assistance when troubleshooting Document Analyzer issues:
- gc-<datetime>.log - Standard Java garbage collection logs (often shows signs of memory issues). By default, this file is rolled over when it exceeds 50 Mb with the last 10 files retained.
Knowledge Model Management (Studio Component) Logging
| Default Configuration File | /opt/semaphore/kmm/webapps/ROOT/WEB-INF/classes/logback.xml (uses the “logback” logging framework, further information is available from logback.qos.ch). |
|---|---|
| Default Log Location | /var/opt/semaphore/kmm/logs/ |
| Log Levels | **TRACE - Most verbose logging DEBUG - Debugging log messages INFO - Information logging messages WARN - Warning messages (recommended setting for production use) ERROR **- Error messages only |
| Log File Name (Default) | SemaphoreWorkbench.log (maximum log size of 1 Mb with log file rotation based upon date/maximum size) |
| Log File Format | YYYY-MM-DD HH:MM:SS.sss [<user>:<connection>] <Message Level> {<Thread>} [<class section>] : <Message text> |
Additional logs in “/var/opt/semaphore/kmm/logs” that may of assistance when troubleshooting Knowledge Model Management issues:
- catalina.log - All nested tomcat instance messages are logged here. The information found here is configured by “/etc/opt/semaphore/kmm/logback-tomcat.xml” (this facility makes use of “logback” logging framework, for more information see logback.qos.ch).
- catalina.out - Back-end (Tomcat) Catalina server containing all events.
- gc-<datetime>.log - Standard Java garbage collection logs (often shows signs of memory issues). By default, this file is rolled over when it exceeds 50 Mb with the last 10 files retained.
- localhost-access.log - Access logs for KMM, that is, all web accesses to Knowledge Model Management are logged here. The information found here is configured by “/etc/opt/semaphore/kmm/logback-access.xml” (this facility makes use of “logback” logging framework, for more information see logback.qos.ch). By default, this file is rolled over (and compressed) when it exceeds 20 Mb with the last 60 files retained.
- localhost.log - Default back-end (Tomcat) log containing log events from the default application (Studio). By default, this file is rolled over (and compressed) when it exceeds 20 Mb with the last 60 files retained.
- SemaphoreSparql.log - A record of all SPARQL execution (including reports). Configured in “/opt/semaphore/kmm/webapps/ROOT/WEB-INF/classes/logback.xml” (uses the “logback” logging framework, further information is available from logback.qos.ch).
Publisher Plugin Logging
| Default Log Location | /var/opt/semaphore/kmm/logs/publisher-logs/ |
|---|---|
| Log File Name | PublisherPlugin-<model name>-<date time of publish>.log |
| Log File Format | YYYY-MM-DD HH:MM:SS,sss [:] <log level> [<section>] <Module Name>:<Line Number> - <Message text> |
Rulenet Manager (Studio Component) Logging
| Default Log Location | /var/opt/semaphore/rm/logs/ |
|---|---|
| Log File Name (Default) | RM.log (log file rotation based upon date) |
| Log File Format | YYYY-MM-DD HH:MM:SS.sss <Message Level> [<section>] <class section> - <Message text> |
Additional logs in “/var/opt/semaphore/rm/logs” that may of assistance when troubleshooting Rulenet Manager issues:
- gc-<datetime>.log - Standard Java garbage collection logs (often shows signs of memory issues). By default, this file is rolled over when it exceeds 50 Mb with the last 10 files retained.
Semantic Enhancement Server Logging
| Default Logging Configuration Files | /opt/semaphore/SES/solr/server/resources/log4j.properties (uses the “log4j” logging framework, further information is available from log4j). |
|---|---|
| Default Log Location | /var/opt/semaphore/SES/logs/ |
| Log Levels | **DEBUG - Most verbose logging INFO - Informational logging messages WARN - Warning messages (recommended for production environments) ERROR **- Error messages only |
| Log File Name | solr.log - Contains the log for the running SoLR instance hosting SES. Rolled over when it exceeds 32 Mb (and up to 10 files kept). |
| Log File Format | Layout is configurable in the configuration file, default is as follows: YYYY-MM-DD HH:MM:SS,sss <log level> (section) [<core reference>] <Module Name> <Message text> |
Additional log files in “/var/opt/semaphore/SES/logs” that may of assistance when troubleshooting Semantic Enhancement Server issues:
- SESAcccess.log - Access logs for SES requests. Configured in “/opt/semaphore/SES/solr/server/resources/log4j.properties” (uses the “log4j” logging mechanism, further information is available from log4j). Rolled over when it exceeds 32 Mb (and up to 10 files kept).
- solr_gc.log - Standard Java garbage collection logs (often shows signs of memory issues). By default, this file is rolled over when it exceeds 20 Mb with the last 9 files retained.
- solr_slow_requests.log - A lot of all slow requests. Rolled over when it exceeds 32 Mb (and up to 10 files kept).
SES Manager (Studio Component) Logging
| Default Log Location | /var/opt/semaphore/sm/logs/ |
|---|---|
| Log File Name (Default) | SM.log (log file rotation based upon date) |
| Log File Format | YYYY-MM-DD HH:MM:SS.sss <Message Level> [<section>] <class section> - <Message text> |
Additional logs in “/var/opt/semaphore/sm/logs” that may of assistance when troubleshooting SES Manager issues:
- gc-<datetime>.log - Standard Java garbage collection logs (often shows signs of memory issues). By default, this file is rolled over when it exceeds 50 Mb with the last 10 files retained.
Studio Logging
| Default Configuration File | /opt/semaphore/studio/webapps/ROOT/WEB-INF/classes/logback.xml |
|---|---|
| Default Log Location | /var/opt/semaphore/studio/logs/ |
| Log Levels | **TRACE - Most verbose logging DEBUG - Debugging log messages INFO - Information logging messages WARN - Warning messages (recommended setting for production use) ERROR **- Error messages only |
| Log File Name (Default) | Studio.log (maximum log size of 1 Mb with log file rotation based upon date/maximum size) |
| Log File Format | YYYY-MM-DD HH:MM:SS.sss [<user>:<connection>] <Message Level> {<Thread>} [<class section>] : <Message text> |
Additional logs in “/var/opt/semaphore/studio/logs” that may of assistance when troubleshooting Studio issues:
- catalina.log - All nested tomcat instance messages are logged here. The information found here is configured by “/etc/opt/semaphore/studio/logback-tomcat.xml” (this facility makes use of “logback” logging framework, for more information see logback.qos.ch).
- catalina.out - Back-end (Tomcat) Catalina server containing all events.
- gc-<datetime>.log - Standard Java garbage collection logs (often shows signs of memory issues). By default, this file is rolled over when it exceeds 50 Mb with the last 10 files retained.
- localhost-access.log - Access logs for studio, that is, all web accesses to Studio are logged here. The information found here is configured by “/etc/opt/semaphore/studio/logback-access.xml” (this facility makes use of “logback” logging framework, for more information see logback.qos.ch). By default, this file is rolled over (and compressed) when it exceeds 20 Mb with the last 60 files retained.
- localhost.log - Default back-end (Tomcat) log containing log events from the default application (Studio). By default, this file is rolled over (and compressed) when it exceeds 20 Mb with the last 60 files retained.