I am using mariadb for my openstack (using CentOS 7). It was working well for almost a month. And it survived many reboots of my server. But last week there was an outage in server and since then I cannot start my mariadb.I am getting below error:$ systemctl start mariadb.service Job for mariadb.service failed because the control process exited with error code. See systemctl status mariadb.service and journalctl -xe for details.$ systemctl status mariadb.service -l mariadb.service - MariaDB database server   Loaded: loaded (/usr/lib/systemd/system/mariadb.service; enabled; vendor preset: disabled)   Active: failed (Result: exit-code) since Tue 2016-02-16 15:11:26 EST; 7s ago  Process: 9038 ExecStartPost=/usr/libexec/mariadb-wait-ready $MAINPID (code=exited, status=1/FAILURE)  Process: 9037 ExecStart=/usr/bin/mysqld_safe --basedir=/usr (code=exited, status=1/FAILURE)  Process: 9009 ExecStartPre=/usr/libexec/mariadb-prepare-db-dir %n (code=exited, status=0/SUCCESS) Main PID: 9037 (code=exited, status=1/FAILURE)Feb 16 15:11:25 LAB mysqld_safe[9037]: 160216 15:11:25 mysqld_safe Logging to '/var/log/mariadb/mariadb.log'.Feb 16 15:11:25 LAB mysqld_safe[9037]: 160216 15:11:25 mysqld_safe Starting mysqld daemon with databases from /var/lib/mysqlFeb 16 15:11:25 LAB mysqld_safe[9037]: 160216 15:11:25 mysqld_safe WSREP: Running position recovery with --log_error='/var/lib/mysql/wsrep_recovery.D276kI' --pid-file='/var/lib/mysql/LAB-recover.pid'Feb 16 15:11:25 LAB mysqld_safe[9037]: 160216 15:11:25 mysqld_safe WSREP: Failed to recover position:Feb 16 15:11:25 LAB mysqld_safe[9037]: ''Feb 16 15:11:25 LAB systemd[1]: mariadb.service: main process exited, code=exited, status=1/FAILUREFeb 16 15:11:26 LAB systemd[1]: mariadb.service: control process exited, code=exited status=1Feb 16 15:11:26 LAB systemd[1]: Failed to start MariaDB database server.Feb 16 15:11:26 LAB systemd[1]: Unit mariadb.service entered failed state.Feb 16 15:11:26 LAB systemd[1]: mariadb.service failed.Can you please help me to fix this issue?Below are the contents of /var/log/mariadb/mariadb.log:[root@LAB cisco]# tail -f /var/log/mariadb/mariadb.log160216 15:31:21 mysqld_safe WSREP: Running position recovery with --log_error='/var/lib/mysql/wsrep_recovery.DtEKRY' --pid-file='/var/lib/mysql/LAB-recover.pid'nohup: ignoring input/usr/libexec/mysqld: symbol lookup error: /usr/libexec/mysqld: undefined symbol: _ZN22File_parser_dummy_hook22process_unknown_stringERPcPhP11st_mem_rootS0_160216 15:31:21 mysqld_safe WSREP: Failed to recover position: ''160216 15:36:08 mysqld_safe Starting mysqld daemon with databases from /var/lib/mysql160216 15:36:08 mysqld_safe WSREP: Running position recovery with --log_error='/var/lib/mysql/wsrep_recovery.sNBKaQ' --pid-file='/var/lib/mysql/LAB-recover.pid'/usr/libexec/mysqld: symbol lookup error: /usr/libexec/mysqld: undefined symbol: _ZN22File_parser_dummy_hook22process_unknown_stringERPcPhP11st_mem_rootS0_160216 15:36:08 mysqld_safe WSREP: Failed to recover position: ''
mariadb.service: main process exited, code=exited, status=1/FAILURE(Centos7)
mariadb;openstack