Logs
Denodo uses log4j to generate the log files for its servers. The logs for the Virtual DataPort server are located in the installation folder, under logs/vdp.log. This is the first place to look when an error takes place in the server.
The log4j configuration file can be modified if needed, changing the logging levels or the max historical data that is stored, modifying the file conf/vdp/log4j.xml
JMX
It is possible to access server monitoring information using the Java Management extensions (JMX) standard. This information can be used to control the use of the server and audit the actions carried out on the data sources and/or the Virtual DataPort metadata.
The available monitoring information is:
- General information on the server: number of active and inactive connections, memory usage, etc.
- Configuration and accesses to the server cache.
- Accesses to each data source.
- Accesses to the views and stored procedures.
- Transactions executed by the Virtual DataPort server.
Virtual DataPort also generates different types of JMX notifications whenever:
- A DDL statement is executed. E.g. ALTER TABLE, CREATE VIEW, etc.
- A DML statement is executed. E.g. SELECT, INSERT, etc.
- Transactions start or end.
External monitoring applications using JMX like HP Open View, NAGIOS, Cacti, etc can be set up to monitor the state of the server in real time.