Hi, Andrei! fdle changes - ok, I've seen them in 21117. cur_log/etc - clear. What are the changes around prev_event_pos for? On Jul 23, Andrei Elkin wrote:

revision-id: 412e696fd2b (mariadb-10.3.26-136-g412e696fd2b) parent(s): 2fa526e26e8 author: Andrei Elkin committer: Andrei Elkin timestamp: 2021-04-15 17:11:07 +0300 message:

MDEV-25395 server recovery hits replication event checksum error

When @@global.binlog_checksum is changing from none to crc32 and only the first of two Binlog_checkpoint_log_event gets written to the crc32 rotated binlog file before the server crashes, the recovery faces a checksum verification error.

The reason was that recovery algorithm did not realize potentially varying binlog checksum at scanning of a sequence of binlog files.

That is corrected now. The master-checksum-verify server recovery aborts now and stops the server due to the checksum error. A simulation test confirms the fixes.

Induced changes:

rpl_cant_read_event_incident got affected because the test adopts an external not properly closed binlog file that contains events which can't pass checksum verification. A work-around is done to accept that binlog and evade recovery.

binlog_recover_checksum_error needed refinement as the master-checksum-verify configured server is made to stop due to the checksum error.

Regards, Sergei VP of MariaDB Server Engineering and security@mariadb.org