This can happen for a variety of reasons. Please troubleshoot the issue by following the steps below one by one. 1) Verify the address mysql is bound to, it’s probably 127.0.0.1 (only) which I believe is the default (at least on standard Ubuntu server). You’ll have to comment out the… Continue Reading [ERROR][logstash.inputs.jdbc Unable to connect to database. Tried 1 times {:error_message=>”Java::ComMysqlJdbcExceptionsJdbc4::CommunicationsException: Communications link failure\n\nThe last packet successfully received from the server was 1 milliseconds ago. The last packet sent successfully to the server was 1 milliseconds ago.”}