MHA Manager

Changes in Manager 0.53 (Jan 9 2012)

New features:
Manager-Issue#12 Supporting RESET SLAVE ALL from MySQL 5.5.16
Manager-Issue#15 Supporting "skip_reset_slave" parameter to avoid running CHANGE MASTER TO on the promoted slave
Manager-Issue#18 Checking master's ping status via CONNECT, in addition to SELECT
Supporting --check_only for online master switch / patch
Supporting "mysql --binary-mode" from MySQL 5.6.3 / patch
Supporting ssh_host and ssh_port parameters / patch
Supporting ssh_options parameter / patch
When doing online master switch, MHA checks whether long queries are running on the new master. This is important to reduce workloads on the new master. Query time limit can be controlled via --running_seconds_limit. / patch
When executing SIGINT on online master switch, MHA tries to disconnect established connections via MHA. / patch
Additionally checking replication filtering rules on online master switch / patch

Bug fixes:
Manager-Issue#13 MHA Manager looks for relay-log.info in wrong location
Manager-Issue#14 Wrong option for master_ip_failover_script
Manager-Issue#17 Timeout settings for SSH connection health check does not always work
Modifying a rpm spec file to create valid rpm package for 64bit RHEL6 / patch
Manager-Issue#19 Forcing more strict ssh checking. Originally MHA checks master's reachability by just connecting via SSH and exiting with return code 0. This in some cases does not work especially if SSH works but data files are not accessible. In this fix, MHA checks master's ssh reachability by executing save_binary_logs command (dry run). MHA Client also needs to be updated to 0.53.
Zombie process remains on master ping timeout / patch
Do not execute SET GLOBAL read_only=(0|1) if not needed / patch
     SET GLOBAL read_only=(0|1) conflicts with long running queries
    and will block all updates (including from root and SQL Thread)
    until conflicting queries finish. In theory this should happen
    only when setting from 0 to 1, and 5.5 works correcty,
    but current 5.1 locks anytime (including 0->0, 1->1, 1->0).
    This is dangerous and do not run SET GLOBAL read_only=(0|1)
    if not needed.
    MHA should execute SET GLOBAL read_only in the below cases:
    - Online master switch: SET GLOBAL read_only=1 on the current master
    (from master_ip_online_change script)
    - Failover and online master switch: SET GLOBAL read_only=0
    on the new master if current read_only value is 1

    On online master switch, FLUSH NO_WRITE_TO_BINLOG TABLES
    will be executed (manually) beforehand, so this issue will
    rarely happen.

Changes in Manager 0.52 (Sep 16 2011)

Package name change:
Package name has changed from "MySQL-MasterHA-Manager-X.Y" to "mha4mysql-manager-X.Y". This is to avoid potential trademark issues.

New features:
Manager-Issue#5 Supporting multi-master configuration

Bug fixes:
Manager-Issue#6 masterha_check_repl may die with UUV when a master dies
Manager-Issue#8 MHA Manager does not start if Log::Dispatch version is 2.22 or lower
Manager-Issue#10 @@global.relay_log_purge should be preserved on change master
Manager-Issue#11 Manager aborts by UUV if errstr is empty (rare cases)

Misc:
Manager-Issue#7 Connection checks are done in parallel. Failover can be done much faster when multiple MySQL servers are not reachable.
Followed Perl Best Practices

Changes in Manager 0.51 (Aug 18 2011)

Bug fixes:
Manager-Issue#4 Some tentative working files were written in a current directory, not working directory
Manager-Issue#3 Checking slave state string is incorrect for MySQL 5.5+. This might stop slave recovery.
Manager-Issue#2 Wrong exit code on masterha_manager
Manager-Issue#1 When multiple servers with the same hostname and different ports are defined, migration information is not printed correctly

Misc:
Public test cases are added.

Changes in Manager 0.50 (Jul 23 2011)

Initial Public Release

MHA Node

Changes in Node 0.53 (Jan 9 2012)

New features:
Issue#3 Supporting "mysql --binary-mode" from MySQL 5.6.3
Supporting ssh_host and ssh_port parameters
Supporting ssh_options parameter

Bug fixes:
Issue#2 MHA Manager looks for relay-log.info in wrong location
Issue#4 Forcing more strict ssh checking.

Changes in Node 0.52 (Sep 16 2011)

Package name change:
Package name has changed from "MySQL-MasterHA-Node-X.Y" to "mha4mysql-node-X.Y". This is to avoid potential trademark issues.

Misc:
Followed Perl Best Practices

Version 0.51 has skipped.

Changes in Node 0.50 (Jul 23 2011)

Initial Public Release

RPM packages:
Node-Issue#1 Node rpm package should not depend on MODULE_COMPAT
RPM packages for RH4,5,6