Database is not connecting when trying to install oozie using ambari..

[#1]

2019-06-27 03:39:42,688 - Check db_connection_check was unsuccessful. Exit code: 1. Message: ERROR: Unable to connect to the DB. Please check DB connection properties. com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure 
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server. 
Traceback (most recent call last):  File "/var/lib/ambari-agent/cache/custom_actions/scripts/check_host.py", line 546, in <module>    CheckHost().execute()  File "/usr/lib/ambari-agent/lib/resource_management/libraries/script/script.py", line 375, in execute    method(env)  File "/var/lib/ambari-agent/cache/custom_actions/scripts/check_host.py", line 207, in actionexecute    raise Fail(error_message) resource_management.core.exceptions.Fail: Check db_connection_check was unsuccessful. Exit code: 1. Message: ERROR: Unable to connect to the DB. Please check DB connection properties. com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure 
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server

[#2 · Accepted solution]

@Alampally Vinith

The error indicates that your MySQL Server seems may not be running healthy. The MYSQl server is not responding to the jdbc call of the driver.

Please check DB connection properties. com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure 
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server

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Please try to restart your MySQL Server and then verify the mysql connectivity from oozie host.

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