title: MariaDB Not Starting: "Plugin 'FEEDBACK' is disabled."
body: <p>I installed MariaDB 10.2.10 on CentOS 7 but it stopped running. If I do:</p>
  
  <p>If I do:</p>
  
  <pre><code>systemctl restart mariadb.service
  </code></pre>
  
  <p>I get:</p>
  
  <pre><code>mariadb.service: main process exited, code=killed, status=6/ABRT
  Failed to start MariaDB 10.2.12 database server.
  Unit mariadb.service entered failed state.
  </code></pre>
  
  <p>What's weird is that it was running fine for more than a year and now suddenly, it won't start. It's a production server, so I have several databases there that I need; I can't just reinstall it from scratch.</p>
  
  <p>What can I do to get MariaDB back up and running without losing my databases?</p>
  
  <h2>/var/log/messages</h2>
  
  <pre><code>systemd: mariadb.service: main process exited, code=killed, status=6/ABRT
  Asystemd: Failed to start MariaDB 10.2.12 database server.
  Asystemd: Unit mariadb.service entered failed state.
  Asystemd: mariadb.service failed.
  systemd: mariadb.service holdoff time over, scheduling restart.
  systemd: Starting MariaDB 10.2.12 database server...
  mysqld: 2018-04-24  7:06:38 140101542774912 [Note] /usr/sbin/mysqld (mysqld 10.2.12-MariaDB) starting as process 24976 ...
  mysqld: 2018-04-24  7:06:38 140101542774912 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins
  mysqld: 2018-04-24  7:06:38 140101542774912 [Note] InnoDB: Uses event mutexes
  mysqld: 2018-04-24  7:06:38 140101542774912 [Note] InnoDB: Compressed tables use zlib 1.2.7
  mysqld: 2018-04-24  7:06:38 140101542774912 [Note] InnoDB: Using Linux native AIO
  mysqld: 2018-04-24  7:06:38 140101542774912 [Note] InnoDB: Number of pools: 1
  mysqld: 2018-04-24  7:06:38 140101542774912 [Note] InnoDB: Using SSE2 crc32 instructions
  mysqld: 2018-04-24  7:06:38 140101542774912 [Note] InnoDB: Initializing buffer pool, total size = 128M, instances = 1, chunk size = 128M
  mysqld: 2018-04-24  7:06:38 140101542774912 [Note] InnoDB: Completed initialization of buffer pool
  mysqld: 2018-04-24  7:06:38 140100781233920 [Note] InnoDB: If the mysqld execution user is authorized, page cleaner thread priority can be changed. See the man page of setpriority().
  mysqld: 2018-04-24  7:06:38 140101542774912 [Note] InnoDB: Log sequence number at the start 1597389266 and the end 1597386521 do not match
  mysqld: 2018-04-24  7:06:38 140101542774912 [ERROR] InnoDB: Database page corruption on disk or a failed file read of tablespace innodb_system page [page id: space=0, page number=5]. You may have to recover from a backup.
  mysqld: 2018-04-24  7:06:38 140101542774912 [Note] InnoDB: Uncompressed page, stored checksum in field1 2317626450, calculated checksums for field1: crc32 2317626450/1916606668, innodb 3858799490,  page type 7 == TRX_SYS.none 3735928559, stored checksum in field2 960005681, calculated checksums for field2: crc32 2317626450/1916606668, innodb 756644076, none 3735928559,  page LSN 0 1597389266, low 4 bytes of LSN at page end 1597386521, page number (if stored to page already) 5, space id (if created with &gt;= MySQL-4.1.1 and stored already) 0
  mysqld: InnoDB: Page may be a transaction system page
  mysqld: 2018-04-24  7:06:38 140101542774912 [Note] InnoDB: It is also possible that your operating system has corrupted its own file cache and rebooting your computer removes the error. If the corrupt page is an index page. You can also try to fix the corruption by dumping, dropping, and reimporting the corrupt table. You can use CHECK TABLE to scan your table for corruption. Please refer to http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html for information about forcing recovery.
  mysqld: 2018-04-24  7:06:38 140101542774912 [ERROR] [FATAL] InnoDB: Aborting because of a corrupt database page.
  mysqld: 180424  7:06:38 [ERROR] mysqld got signal 6 ;
  mysqld: This could be because you hit a bug. It is also possible that this binary
  mysqld: or one of the libraries it was linked against is corrupt, improperly built,
  mysqld: or misconfigured. This error can also be caused by malfunctioning hardware.
  mysqld: To report this bug, see https://mariadb.com/kb/en/reporting-bugs
  mysqld: We will try our best to scrape up some info that will hopefully help
  mysqld: diagnose the problem, but since we have already crashed,
  mysqld: something is definitely wrong and this may fail.
  mysqld: Server version: 10.2.12-MariaDB
  mysqld: key_buffer_size=134217728
  mysqld: read_buffer_size=131072
  mysqld: max_used_connections=0
  mysqld: max_threads=153
  mysqld: thread_count=0
  mysqld: It is possible that mysqld could use up to
  mysqld: key_buffer_size + (read_buffer_size + sort_buffer_size)*max_threads = 467244 K  bytes of memory
  mysqld: Hope that's ok; if not, decrease some variables in the equation.
  mysqld: Thread pointer: 0x0
  mysqld: Attempting backtrace. You can use the following information to find out
  mysqld: where mysqld died. If you see no messages after this, something went
  mysqld: terribly wrong...
  mysqld: stack_bottom = 0x0 thread_stack 0x49000
  mysqld: /usr/sbin/mysqld(my_print_stacktrace+0x2e)[0x557c611fdc4e]
  mysqld: /usr/sbin/mysqld(handle_fatal_signal+0x355)[0x557c60c88825]
  mysqld: /lib64/libpthread.so.0(+0xf5e0)[0x7f6bee7195e0]
  mysqld: /lib64/libc.so.6(gsignal+0x37)[0x7f6becc261f7]
  mysqld: /lib64/libc.so.6(abort+0x148)[0x7f6becc278e8]
  mysqld: /usr/sbin/mysqld(+0x9a5643)[0x557c60fc2643]
  mysqld: /usr/sbin/mysqld(+0x9e7289)[0x557c61004289]
  mysqld: /usr/sbin/mysqld(+0xa0adfa)[0x557c61027dfa]
  mysqld: /usr/sbin/mysqld(+0x9e8986)[0x557c61005986]
  mysqld: /usr/sbin/mysqld(+0x9888af)[0x557c60fa58af]
  mysqld: /usr/sbin/mysqld(+0x9575ab)[0x557c60f745ab]
  mysqld: mysys/stacktrace.c:268(my_print_stacktrace)[0x557c60f76d87]
  mysqld: buf/buf0buf.cc:6026(buf_page_io_complete(buf_page_t*, bool))[0x557c60e62cf9]
  mysqld: buf/buf0rea.cc:227(buf_read_page(page_id_t const&amp;, page_size_t const&amp;))[0x557c60c8ace4]
  mysqld: srv/srv0start.cc:896(srv_undo_tablespaces_init(bool))[0x557c60b0b3c0]
  mysqld: /usr/sbin/mysqld(_Z11plugin_initPiPPci+0x9a2)[0x557c60b0cc72]
  mysqld: handler/ha_innodb.cc:4381(innobase_init(void*))[0x557c60a66be8]
  mysqld: sql/handler.cc:520(ha_initialize_handlerton(st_plugin_int*))[0x557c60a6b2d1]
  mysqld: sql/sql_plugin.cc:1411(plugin_initialize(st_mem_root*, st_plugin_int*, int*, char**, bool))[0x7f6becc12c05]
  mysqld: sql/mysqld.cc:5258(init_server_components())[0x557c60a5f51d]
  mysqld: The manual page at http://dev.mysql.com/doc/mysql/en/crashing.html contains
  mysqld: information that should help you find out what is causing the crash.
  systemd: mariadb.service: main process exited, code=killed, status=6/ABRT
  systemd: Failed to start MariaDB 10.2.12 database server.
  systemd: Unit mariadb.service entered failed state.
  systemd: mariadb.service failed.
  </code></pre>