It is expected you have a good understanding the database connection pool and trouble-shooting techniques before enabling Verify Source
What is JDBC Verify & Verify Sources and how does it work?
Both are referenced here as they work the same behind the scenes, though please be aware these options are independent of eachother.
JDBCVerify & Verify Source is a configuration setting that tells Yellowfin to check all active connections with background scheduled task, this runs every minute. It checks the connections by returning the schema (no data), if the schema is not returned the connection is removed from the in-use pool. This can be turned on for the Yellowfin DB connection, 'JDBCVERIFY', as well as data sources, 'VERIFYSOURCE'.
Do I need it?
....maybe. It's important to remember that bad connections should be fixed at the underlying cause, not worked around. We do however understand this can still be useful in cases where the network is a little flaky. Though there are still some important things to note before enabling this:
- It checks both the data sources and Yellowfin DB connection.
- This can affect performance of the DB server itself.
- It's a background task, so it's running whether you are using the system or not.
- If you're only interested in data source connections, volatile sources is a better option.
How do I enable and configure it?
If you're at this point, it's expected that you understand how the connection pool works, and that you've determined this will help. To enable these options you will be making changes to your web.xml and/or Yellowfin Config DB, so please ensure you make a backup before proceeding. Remember these are 2 different options and run independent of each other.
- JDBC Verify
This is enabled by added the following section to the web.xml within the connection pool servlet.
<init-param> <param-name>JDBCVerify</param-name> <param-value>true</param-value> </init-param>
e.g
Once you've made this change, restart the Yellowfin service.
- Verify Sources
This is done by inserting a row into the configuration database.
INSERT INTO Configuration (iporg, configtypecode, configcode, configdata) VALUES (1, 'SYSTEM', 'VERIFYSOURCE', 'TRUE');
Once you've made this change, restart the Yellowfin service.
To confirm the options have been enabled, you can check the JDBC or Source logs for the following entry:
If you have any questions, or running into issues relating to connections, please raise a ticket with our support team.
Regards,
The Yellowfin Support Team.