FAILOVER_TYPE and FAILOVER_METHOD Are Null When Connecting With JDBC Thin With FAILOVER_MODE (Doc ID 2264622.1)

Last updated on MAY 31, 2023

Applies to:

Symptoms

JDBC thin client does not use failover configuration to connect to the database, and it is not failing over to available database instance when original instance is down.
The JDBC connection string used is:

Checking out gv$session, those connections from JDBC thin show failover_type => NULL and failover_method=>NULL, and they do not switch over to available instance.

 
JDBC connections are expected to fail over to available node.


STEPS
-----------------------
The issue can be reproduced at will with the following steps:
1. Configure connection string as:
jdbc:oracle:thin:@(DESCRIPTION=(LOAD_BALANCE=on)(FAILOVER=on)(ADDRESS=(PROTOCOL=TCP)(HOST=<SCAN HOSTNAME>)(PORT=<PORT>))(CONNECT_DATA=(SERVER=DEDICATED)(SERVICE_NAME=<SERVICE NAME>)(FAILOVER_MODE=(TYPE=SELECT)(METHOD=BASIC)(RETRIES=5)(DELAY=180))))
2. Run connections.
3. Check out gv$session, those connections from JDBC thin -- failover_type => NULL and failover_method=>NULL
4. Bring one node down -- those connections do not switch over to available instance.

Changes

Cause

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