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DBConnect : Unable to connect to Oracle database Network Adaptor could not establish connection

lakshman239
Influencer

Hi,

 I have following setup.

  • Splunk HF running on 9.1.2
  • Splunk Dbconnect latest version - 3.15
  • Splunk DBX Add on for oracle DB JDBC - 2.2.0 ( has ojdbc8-21.7.0.0.jar)
  • Configured to use JRE from Oracle's Open jdk-18.0.2
  • Our Oracle database is running on 19c.

 I have re-loaded the driver. I have verified the connectivity from the Splunk HF server to DB server via telnet/curl and connection exists ( had to open firewall).

However, when I try create a connection getting errors like "IO Error: Network Adapater could not establish connection) from the internal logs. 

Suspected, it could be an issue with jdbc driver, so downloaded "ojdbc8-21.1.0.0.jar" from oracle and placed them under drivers folder within splunk_app_db_connect as well as in the lib folder within the DBX add-on. re-loaded the driver and I can see internal logs loading the new jar, but still same issue.

Any pointers/thoughts to troubleshoot?

java.sql.SQLRecoverableException: IO Error: The Network Adapter could not establish the connection (CONNECTION_ID=5gNEcEZfSnyI6PN7r2LGog==) at oracle.jdbc.driver.T4CConnection.handleLogonNetException(T4CConnection.java:892) at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:697) at oracle.jdbc.driver.PhysicalConnection.connect(PhysicalConnection.java:1041) at oracle.jdbc.driver.T4CDriverExtension.getConnection(T4CDriverExtension.java:89) at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:732) at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:648) at com.splunk.dbx.service.driver.DelegatingDriver.connect(DelegatingDriver.java:25)

Thanks in advance.

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1 Solution

lakshman239
Influencer

Answering my query, as I hope this could help others.

The oracle 19c RAC database had SCAN address ( Single Client Access Name ) and needed additional firewall rules from the splunk servers to actual physical oracle servers, as the jdbc driver in dbconnect needs access to it to establish connection. Once firewall rules are implemented, dbconnect worked.

View solution in original post

0 Karma

viku7474
Explorer

Hi @lakshman239 
Thanks for the info.
Can you provide some more insights? What are the additional rules?

I have a similar request and I am able to telnet on 1521 port from splunk, but still the connectivity says it is blocked by firewall while submitting..

0 Karma

lakshman239
Influencer

The firewall request from the splunk server (e.g. HF) should be both to the actual database physical host/IPs and  the SCAN host/IP server. ( if using this in the tns listener files). In a RAC setup there may be multiple IP/host, so you would need access to all of them from splunk server. Another test would be to run a nslookup on the scan ip/hostname/FQDN and if it return multiple IPs/host, submit firewall req for them as well.

0 Karma

lakshman239
Influencer

Answering my query, as I hope this could help others.

The oracle 19c RAC database had SCAN address ( Single Client Access Name ) and needed additional firewall rules from the splunk servers to actual physical oracle servers, as the jdbc driver in dbconnect needs access to it to establish connection. Once firewall rules are implemented, dbconnect worked.

0 Karma
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