"FLUSH ENGINE LOGS" bring inconsistency into GTID-enabled slave

[Denis Zhdanov]

When I backup Percona Server 5.6.21 on slave with percona-xtrabackup 2.2.5, I find that innobackupex executes the command：
'FLUSH ENGINE LOGS'
this command will be record to slave binlog，which leads to inconsistency between master and slave when GTID enabled.

Suggested fix:
Replace the line :
mysql_query(\%mysql, "FLUSH ENGINE LOGS");
with
mysql_query(\%mysql, "FLUSH NO_WRITE_TO_BINLOG ENGINE LOGS");

I have test it, and it doesn't record "FLUSH ENGINE LOGS" to slave binlog.

(Based on http://www.percona.com/forums/questions-discussions/percona-xtrabackup/24993-percona-xtrabackup-2-2-4-innobackup-update, but I hit same bug recently)

[Alexey Kopytov (akopytov)]

Thank you for the bug report. This has also been reported as bug #1384140, but it didn't occur to us that the inconsistency is in the binary log coordinates, rather than data. I have marked that bug as a duplicate of this one.

[Denis Zhdanov (deniszhdanov)]

Of course, it will create "inconsistency is in the binary log",i.e. create new transaction on slave which become errant transaction instantly (http://www.percona.com/blog/2014/05/19/errant-transactions-major-hurdle-for-gtid-based-failover-in-mysql-5-6/) and blocks failover until we fix it.

[pako (pakonet)]

We have exactly the same problem. We cannot use Xtrabackup 2.3.1-beta1 on a MySQL slave in a GTID enabled replication setup. Executing:

FLUSH NO_WRITE_TO_BINLOG ENGINE LOGS

adds an errant transaction and we start getting notifications from our monitoring system. At this point we have to fix the "Executed_Gtid_Set" value on the slave or inject empty transactions on all other servers. This is not easy to do, so for now we decided against using Xtrabackup on MySQL slaves.

[Denis Zhdanov (deniszhdanov)]

pako, fix was released in stable version 2.2.7 too.
If you can't migrate to it - just edit percona-xtrabackup and
replace the line :
mysql_query(\%mysql, "FLUSH ENGINE LOGS");
with
mysql_query(\%mysql, "FLUSH NO_WRITE_TO_BINLOG ENGINE LOGS");

[Shahriyar Rzayev (rzayev-sehriyar)]

Percona now uses JIRA for bug reports so this bug report is migrated to: https://jira.percona.com/browse/PXB-415