Cisco Cisco Workload Automation 6.3 Guida Utente
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Cisco Systems, Inc.
www.cisco.com
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Troubleshooting the MapReduce Adapter
Overview
This chapter describes how to troubleshoot issues for the MapReduce Adapter:
Review Service Log Files for More Information
Refer to the log files for further information regarding an issue.
Connection Failures
Verify the hostname to IP address mappings in the hosts file
For secured connections, verify service.props has been correctly set up to support Kerberos.
Verify that the user keytab file exists and is accessible to CWA master.
If you are using MapR, verify that the Hadoop instance is running using Java 8. Also verify that the MapR client is configured
correctly. See
correctly. See
for details.
Hadoop:GSSException: No valid credentials provided :Clock skew too great
—
Occurs when the clock skew between the KDC and clients exceed a maximum threshold (default 5 minutes).
Maintaining synchronized clocks between the KDCs and Kerberos clients (TIDAL) is required, therefore Network Time
Protocol (NTP) software or other similar time service tools must be used to synchronize them. Updating the Master's
clock to the KDC server time will temporarily address the issue, but a time service software must be used to keep them
synchronized.
Maintaining synchronized clocks between the KDCs and Kerberos clients (TIDAL) is required, therefore Network Time
Protocol (NTP) software or other similar time service tools must be used to synchronize them. Updating the Master's
clock to the KDC server time will temporarily address the issue, but a time service software must be used to keep them
synchronized.
Job Failures
Verify your job is configured correctly.