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"TNS-12537: TNS:connection closed" frequent error when using JDBC (Doc ID 2771807.1)

Last updated on JUNE 29, 2021

Applies to:

JDBC - Version 12.2.0.0.0 and later
Information in this document applies to any platform.

Symptoms

A JDBC Application is facing TNS connection closed very frequently. JDBC driver 12.2.0.1.0 (ojdbc8.jar) is being used.


Additional details
-----------------------
- No code/configurations changes were done.
- It was working fine. This issue used to occur once/twice a year. After Database migration to Exadata, frequency has increased very much.
- To recover, the job which connects to the Database is re-run.
- There is a firewall between the application and the database.


ERROR
-------
AWKDBE009E Unable to create the connection "IO Error: The Network Adapter could not establish the connection".


Listener log
----------------
 (ADDRESS=(PROTOCOL=tcp)(HOST=<IP-Address>)(PORT=<PORT)) * * 12537
TNS-12537: TNS:connection closed
 TNS-12560: TNS:protocol adapter error
  TNS-00507: Connection closed
  Linux Error: 115: Operation now in progress
::::::::::::
::::::::::::
 (CONNECT_DATA=(CID=(PROGRAM=JDBC Thin Client)(HOST=__jdbc__)(USER=<USER>))(SID=<SID>)) * (ADDRESS=(PROTOCOL=tcp)(HOST=<IP>)(PORT=<PORT>)) * establish *  * 12505
TNS-12505: TNS:listener does not currently know of SID given in connect descriptor


Database alert log
----------------
Fatal NI connect error 12170.

  VERSION INFORMATION:
  TNS for Linux: Version 12.2.0.1.0 - Production
  Oracle Bequeath NT Protocol Adapter for Linux: Version 12.2.0.1.0 - Production
  TCP/IP NT Protocol Adapter for Linux: Version 12.2.0.1.0 - Production
  Tracing not turned on.
  Tns error struct:
  ns main err code: 12535

TNS-12535: TNS:operation timed out
  ns secondary err code: 12560
  nt main err code: 505

TNS-00505: Operation timed out
  nt secondary err code: 110
  nt OS err code: 0
  Client address: (ADDRESS=(PROTOCOL=tcp)(HOST=<IP>)(PORT=<PORT>))
 


JDBC URL:
----------------
oracle.jdbc.OracleDriver
  jdbc:oracle:thin:@(DESCRIPTION_LIST = (LOAD_BALANCE = off) (FAILOVER = on) (DESCRIPTION = (CONNECT_TIMEOUT = 5) (TRANSPORT_CONNECT_TIMEOUT = 3) (RETRY_COUNT = 3) (ADDRESS_LIST = (LOAD_BALANCE = on) (ADDRESS = (PROTOCOL = TCP) (HOST = <HOSTNAME>) (PORT = <PORT>))) (CONNECT_DATA = (SERVICE_NAME = <SERVICE-NAME>))) (DESCRIPTION = (CONNECT_TIMEOUT = 5) (TRANSPORT_CONNECT_TIMEOUT = 3) (RETRY_COUNT = 3) (ADDRESS_LIST = (LOAD_BALANCE = on) (ADDRESS = (PROTOCOL = TCP)(HOST = <HOSTNAME>) (PORT = <PORT>))) (CONNECT_DATA = (SERVICE_NAME = <SERVICE-NAME))))


ENVIRONMENT
------------------
JDBC - ojdbc8.jar - 12.2.0.1.0
JDK - 8.x
DB - 12.2.0.1.0

Cause

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In this Document
Symptoms
Cause
Solution


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