Created 08-07-2024 07:26 AM
I am trying to connect to impala using jdbc from one of the BI tools however ,
The connection being successful sometimes disconnects for a while with below error
Caused by: java.sql.SQLException: [Cloudera][ImpalaJDBCDriver](500593) Communication link failure. Failed to connect to server. Reason: java.net.SocketException: Connection or outbound has closed. ExecuteStatment for query "SELECT a,b from test limit 101".
at com.cloudera.impala.hivecommon.api.HS2Client.handleTTransportException(Unknown Source)
at com.cloudera.impala.hivecommon.api.HS2Client.executeStatementInternal(Unknown Source)
at com.cloudera.impala.hivecommon.api.HS2Client.executeStatement(Unknown Source)
at com.cloudera.impala.hivecommon.dataengine.HiveJDBCNativeQueryExecutor.executeNonRowCountQueryHelper(Unknown Source)
at com.cloudera.impala.hivecommon.dataengine.HiveJDBCNativeQueryExecutor.executeQuery(Unknown Source)
at com.cloudera.impala.hivecommon.dataengine.HiveJDBCNativeQueryExecutor.<init>(Unknown Source)
at com.cloudera.impala.hivecommon.dataengine.HiveJDBCDataEngine.prepare(Unknown Source)
at com.cloudera.impala.jdbc.common.SStatement.executeNoParams(Unknown Source)
at com.cloudera.impala.jdbc.common.BaseStatement.execute(Unknown Source)
at com.cloudera.impala.hivecommon.jdbc42.Hive42Statement.execute(Unknown Source)
at com.ibm.cognos.jdbc.adaptor.BaseStatementAdaptor.execute(BaseStatementAdaptor.java:118)
at com.cognos.xqe.data.providers.relational.jdbc.JDBCTabularResult.createJDBCResultSet(JDBCTabularResult.java:424)
at com.cognos.xqe.data.providers.relational.jdbc.JDBCTabularResult.<init>(JDBCTabularResult.java:285)
... 88 more
The port is 21050 firewall is open and no network errors between two servers
Please suggest what might be the cause
Created 08-08-2024 03:03 AM
Hey @hadoopranger Upon further research, I see the reqs for IBM-Cloudera Impala JDBC Driver here[0a] Lets make sure this is followed.
[0a] https://www.ibm.com/docs/en/cognos-analytics/11.1.0?topic=troubleshooting-cloudera-impala-jdbc-drive...
Since this is intermittent, see if there are any timeouts/retries presents on the BI Application layer or LB layer.
We still want to know how the BI tool is connecting to Impala.
Is it via LB or Impala daemons directly?
If the Impala CLI is working as expected, You can try the following:
1. Timeout/Retries logic on the LB for client connections.
2. Try recreating your JDBC connections and implement retry logic within your app and restart the client app.
3. Also, Attaching the IBM Cognos User Guide for your reference:
https://www.ibm.com/docs/en/SSEP7J_11.1.0/com.ibm.swg.ba.cognos.ag_manage.doc/ca_manage.pdf
If you still need further help, I encourage you contacting contacting IBM Community for specific configs on the Data Sources.
Let us know how it goes.
Cheers
V
Created 08-07-2024 10:36 PM
Please check if you are using loadbalancer URL or connecting with a Impala daemon.
Sometimes loadbalancer URL causes this intermittent issue.
Created 08-08-2024 12:26 AM
Hello @hadoopranger Thank you for bringing this to our community.
As you highlight, this looks to be intermittent connectivity issue with the Impala and the Client(BI Tool).
Q. May we know what is the name and version of BI tool you are using?
Also, You may want to review some of the related parameters/configuration from the tool.
Max Wait Time
Max Connection Lifetime
Let us know how it goes.
Cheers
V
Created 08-08-2024 12:38 AM
Hi @vaishaakb thanks for the reply
It is IBM cognos server
I doubt we have these properties available in cognos
Created 08-08-2024 03:03 AM
Hey @hadoopranger Upon further research, I see the reqs for IBM-Cloudera Impala JDBC Driver here[0a] Lets make sure this is followed.
[0a] https://www.ibm.com/docs/en/cognos-analytics/11.1.0?topic=troubleshooting-cloudera-impala-jdbc-drive...
Since this is intermittent, see if there are any timeouts/retries presents on the BI Application layer or LB layer.
We still want to know how the BI tool is connecting to Impala.
Is it via LB or Impala daemons directly?
If the Impala CLI is working as expected, You can try the following:
1. Timeout/Retries logic on the LB for client connections.
2. Try recreating your JDBC connections and implement retry logic within your app and restart the client app.
3. Also, Attaching the IBM Cognos User Guide for your reference:
https://www.ibm.com/docs/en/SSEP7J_11.1.0/com.ibm.swg.ba.cognos.ag_manage.doc/ca_manage.pdf
If you still need further help, I encourage you contacting contacting IBM Community for specific configs on the Data Sources.
Let us know how it goes.
Cheers
V
Created 08-09-2024 12:23 AM
It is connecting via impala daemons directly
Created 08-19-2024 07:34 AM
@hadoopranger I am circling back on this.
Did you try the steps shared in my previous reply? If yes, let us know how did it go.