activemq-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Kyle Miller (JIRA)" <>
Subject [jira] [Commented] (AMQ-4122) Lease Database Locker failover broken
Date Thu, 08 Nov 2012 21:56:13 GMT


Kyle Miller commented on AMQ-4122:

I looked at things a bit closer and realized that there is a bug that is contributing to this
behavior. has a private BrokerService variable.  It
implements BrokerServiceAware and has a method setBrokerService(...). (which extends from LockableServiceSupport)
ALSO has a private BrokerService variable.  It ALSO implements BrokerServiceAware and has
a method setBrokerService(...).  Because it extends from LockableServiceSupport, it overrides
the setter and consequently, the private BrokerService variable will NEVER be set.

I think that the JDBCPersistenceAdapter class should get rid of its private BrokerService
variable (and setter).  This will solve the issue that I was seeing with 2 active master brokers.
> Lease Database Locker failover broken
> -------------------------------------
>                 Key: AMQ-4122
>                 URL:
>             Project: ActiveMQ
>          Issue Type: Bug
>    Affects Versions: 5.7.0
>         Environment: Java 7u9, SUSE 11, Mysql
>            Reporter: st.h
>            Assignee: Gary Tully
>         Attachments: activemq-kyle.xml, activemq.xml, activemq.xml
> We are using ActiveMQ 5.7.0 together with a mysql database and could not observe correct
failover behavior with lease database locker.
> It seems that there is a race condition, which prevents the correct failover procedure.
> We noticed that when starting up two instances, both instance are becoming master.
> We did several test, including the following and could not observe intended functionality:
> - shutdown all instances
> - manipulate database lock that one node has lock and set expiry time in distance future
> - start up both instances. both instances are unable to acquire lock, as the lock hasn't
expired, which should be correct behavior.
> - update the expiry time in database, so that the lock is expired.
> - first instance notices expired lock and becomes master
> - when second instance checks for lock, it also updates the database and becomes master.
> To my understanding the second instance should not be able to update the lock, as it
is held by the first instance and should not be able to become master.

This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see:

View raw message