I received the following error when I
upgraded modified a slave from MySQL 5.6.14 to MariaDB 5.5.33 and executing “START SLAVE;”.
131106 11:12:31 [ERROR] Failed to open the relay log '7' (relay_log_pos 0)
I checked my relay-log.info file and it looked like below…
7 /logs/relay/hostname-relaylog.000046 661930553 hostname-masterlog.000019 661930383 0 0 0
Obviously there a difference in the relay log format, but to get this working, I removed the top line completely (the ‘7’) and I was able to start the slave successfully. Not 100% sure my slave is correctly in sync or error free so be warned of this fix / hack.