3.5. Continuent Tungsten 4.0.4 GA (24 February 2016)

Version End of Life. 31 October 2018

Release Notes 4.0.4 is a bugfix release that contains critical fixes and improvements.

Known Issue

The following issues may affect the operation of Continuent Tungsten and should be taken into account when deploying or updating to this release.

  • For security purposes you should ensure that you secure the following areas of your deployment:

    • Ensure that you create a unique installation and deployment user, such as tungsten, and set the correct file permissions on installed directories. See Directory Locations and Configuration.

    • When using ssh and/or SSL, ensure that the ssh key or certificates are suitably protected. See SSH Configuration.

    • Use a firewall, such as iptables to protect the network ports that you need to use. The best solution is to ensure that only known hosts can connect to the required ports for Continuent Tungsten. For more information on the network ports required for Continuent Tungsten operation, see Network Ports.

    • If possible, use authentication and SSL connectivity between hosts to protext your data and authorisation for the tools used in your deployment. See Deploying SSL Secured Replication and Administration for more information.

  • Under certain circumstances, the rsync process can randomly fail during the installation/ deployment process when using the staging method of deployment. The error code returned by rsync may be 12 or 23.

    The error is transient and non-specific and deployment should be retried.

    Issues: CONT-1343

Improvements, new features and functionality

  • Tungsten Connector

    • The connector has been updated to provide an acknowledgement to the MySQL protocol COM_CHANGE_USER command. This allows client connections that use connection pooling (such as PHP) and the change user command as a verification of an open connection to correctly received an acknowledgement that the connection is available.

      The option is disabled by default. To enable, set the treat.com.change.user.as.ping property to true during configuration with tpm (in [Tungsten Replicator 2.1 Manual]).

      Issues: CONT-1380

      For more information, see Connector Change User as Ping.

Bug Fixes

  • Installation and Deployment

    • When validating the existence of MyISAM tables within a MySQL database, tpm (in [Tungsten Replicator 2.1 Manual]) would use an incorrect method for identifying MyISAM tables. This could lead to MyISAM tables not being located, or legitimate system-related MyISAM tables triggering the alert.

      Issues: CONT-938

  • Core Replicator

    • Binary data contained within an SQL variable and inserted into a table would not be converted correctly during replication.

      Issues: CONT-1412

  • Tungsten Connector

    • A connector running in bridge mode with auto reconnect enabled could try to reconnect to MySQL and attempt additional writes.

      Issues: CONT-1461

    • Automatic retry of query could fail due to interference of keep alive request while re-executing the query.

      Issues: CONT-1512

    • The Tungsten Connector would sometimes retry connectivity on connections that had been killed. The logic has been updated. The default behavior remains the same:

      • Reconnect closed connections

      • Retry autocommitted reads

      The behavior can be modified by using the --connector-autoreconnect-killed-connections (in [Tungsten Replicator 5.0 Manual]). Setting to false disables the reconnection or retry of a connection outside of a planned switch or automatic failover. The default is true, reconnecting and retrying all connections.

      Issues: CONT-1514

  • Tungsten Manager

    • A cluster could go into a panic after a failover if the mysqld and then immediately became available, causing multiple masters to exist.

      Issues: CONT-1482

    • Recovering a node that had been marked as a standby (in [Continuent Tungsten 4.0 Manual]), the node would be recovered into a standard slave, not a standby.

      Issues: CONT-1486

    • The cluster would fail to failover if the interface was down on the master.

      Issues: CONT-1537

    • The embedded Drools libraries have been updated to Drools 6.3. This addresses an issue in Drools which could lead to a memory leak.

      Issues: CONT-1547

Continuent Tungsten 4.0.4 Includes the following changes made in Tungsten Replicator 4.0.4

Continuent Tungsten 4.0.4 is a bugfix release that contains critical fixes and improvements to the Continuent Tungsten 4.0.3 release.

Known Issues

The following issues may affect the operation of Continuent Tungsten and should be taken into account when deploying or updating to this release.

  • Core Replicator

    • Due to a bug within the Drizzle JDBC driver when communicating with MySQL, using the optimizeRowEvents options could lead to significant memory usage and subsequent failure. To alleviate the problem. For more information, see Drizzle JDBC Issue 38.

      Issues: CONT-1115

Bug Fixes

  • Core Replicator

    • When events are filtered on a master, and a slave replicator reconnects to the master, it is possible to get the error server does not have seqno expected by client. The replicator has been updated to correctly supply the sequence number during reconnection.

      Issues: CONT-1384, CONT-1525

    • The timeout used to read information from the MySQL binary logs has been changed from a fixed period of 120 seconds to a configurable parameter. This can be set by using the --property=replicator.extractor.dbms.binlogReadTimeout=180 (in [Tungsten Replicator 2.1 Manual]) property during configuration tpm (in [Tungsten Replicator 2.1 Manual]).

      Issues: CONT-1528

    • When reconnecting within a multi-site multi-master deployment, the session level logging of updates would not be configured correctly in the re-opened session.

      Issues: CONT-1544

    • Within an SOR cluster, an isolated relay site would not resume replication correctly.

      Issues: CONT-1549