MDEV-9423: cannot add new node to the cluser: Binlog..mariadb-10.1.15

.. file '/var/log/mysql/mariadb-bin.000001' not found in binlog
index, needed for recovery. Aborting.

In Galera cluster, while preparing for rsync/xtrabackup based
SST, the donor node takes an FTWRL followed by (REFRESH_ENGINE_LOG
in rsync based state transfer and) REFRESH_BINARY_LOG. The latter
rotates the binary log and logs Binlog_checkpoint_log_event
corresponding to the penultimate binary log file into the new file.
The checkpoint event for the current file is later logged
synchronously by binlog_background_thread.

Now, since in rsync/xtrabackup based snapshot state transfer methods,
only the last binary log file is transferred to the joiner node; the
file could get transferred even before the checkpoint event for the
same file gets written to it. As a result, the joiner node would fail
to start complaining about the missing binlog file needed for recovery.

In order to fix this, a mechanism has been put in place to make
REFRESH_BINARY_LOG operation wait for Binlog_checkpoint_log_event
to be logged for the current binary log file if the node is part of
a Galera cluster. As further safety, during rsync based state transfer
the donor node now acquires and owns LOCK_log for the duration of file
transfer during SST.

1 files changed, 6 insertions, 0 deletions

diff --git a/sql/sql_reload.cc b/sql/sql_reload.cc
index b99ddf45333..e361ed8b6e6 100644
--- a/sql/sql_reload.cc
+++ b/sql/sql_reload.cc
@@ -155,6 +155,12 @@ bool reload_acl_and_cache(THD *thd, unsigned long long options,
     {
       if (mysql_bin_log.rotate_and_purge(true))
         *write_to_binlog= -1;
+
+      if (WSREP_ON)
+      {
+        /* Wait for last binlog checkpoint event to be logged. */
+        mysql_bin_log.wait_for_last_checkpoint_event();
+      }
     }
   }
   if (options & REFRESH_RELAY_LOG)