The following changes have been made to Tungsten Clustering and may affect existing scripts and integration tools. Any scripts or environment which make use of these tools should check and update for the new configuration:
In previous releases, a client
PINGcommand would open a new connection to the MySQL server, execute a
SELECT 1and then returns the OK (or failure) to the client. This could introduce additional load and also affect the metrics if statement execution counts and connections were being monitored.
This has been updated so that the PING request is sent verbatim through to the server by the connector.
The default security configuration for new installations is for security, including SSL and TLS and authentication, to be disabled. In 5.0.0 the default was to enable full security on all components which could lead to problems and difficulty when upgrading.
The following issues may affect the operation of Tungsten Clustering and should be taken into account when deploying or updating to this release.
When performing an upgrade of MySQL 5.6 to MySQL 5.7, and after running mysql_upgrade, the MySQL server must be restarted. Failure to do this could cause switch or failover operations to fail.
Under certain circumstances, the rsyncprocess 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.
tpm has been updated to cope with changes in the configuration and operation of MySQL 5.7.
When performing a persmissions check within tpm, changes to the way password and other information is confirmed has been updated to work correctly with MySQL 5.7. In particular, due to the way passwords are now stored and used, tpm will confirm the configured user and password by checking that login functions correctly.
During installation, tpm will no longer check
the connector credentials if the connector has been configured
to operate in bridge
mode if application specific credentials are not
supplied. If the
are provided, tpm will run the same checks
even if bridge mode has been selected.
Issues: CONT-1580, CONT-1581
The connector has been updated to provide an acknowledgement to
the MySQL protocol
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
configuration with tpm.
For more information, see Section 6.6.6, “Connector Change User as Ping”.
When validating the existence of MyISAM tables within a MySQL database, tpm 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.
The tpm update would fail if the installation directory had been specified with a trailing slash.
If the cluster is put into maintenance mode, but the coordinator node, or the terminal session that put the cluster into maintenance mode fails, the cluster would stay in maintenance mode. The node is now tracked, and if the node goes away for any reason, the cluster will be returned to the mode it was in before being placed into maintenance node.
ERROR >> db2 >> There is already another Tungsten installation script running
The connector would not retry and/or reconnect transactions that were automatically redirected to a slave. This has been corrected so that all slave-targeted requests are retried or reconnected and retried in the event of an error.
Reconnect closed connections
Retry autocommitted reads
The behavior can be modified by using the
the reconnection or retry of a connection outside of a planned
switch or automatic failover. The default is
true, reconnecting and
retrying all connections.
An entity called
appear in the output of ls
resources. This could cause problems with monitoring
tools which parsed the output. The check
script has now been updated to ignore the resource in the
In the event of a mysqld restart, the cluster could recover into a state with multiple masters.
The generated mysql_read_only script would use password on the command line, and could execute a query that returned multiple rows. Both issues could cause issues during executation, particularly for MySQL 5.6 and later.
Tungsten Clustering 5.0.1 is a bugfix release that contains critical fixes and improvements from the Tungsten Clustering 5.0.0 release. Specifically, it changes the default security and other settings to make upgrades from previous releases easier, and other fixes and improvements to the Oracle support and command-line tools.
The following changes have been made to Continuent Replicator and may affect existing scripts and integration tools. Any scripts or environment which make use of these tools should check and update for the new configuration:
The Ruby Net::SSH module, which has been bundled with Tungsten Clustering in past releases, is no longer included. This is due to the wide range of Ruby versions and deployment environments that we support, and differences in the Net::SSH module supported and used with different Ruby versions. In order to simplify the process and ensure that the platforms we support operate correctly, the Net::SSH module has been removed and will now need to be installed before deployment.
To ensure you have the correct environment before deployment, ensure both the Net::SSH and Net::SCP Ruby modules are installed using gem:shell>
gem install net-sshshell>
gem install net-scp
Depending on your environment, you may also need to install the
gem install io-console
If during installation you get an error similar to this:mkmf.rb can't find header files for ruby at /usr/lib/ruby/include/ruby.hshell>
sudo apt install ruby-dev
For compatibility with MySQL 5.7, the tpm command will now check for the
super_read_onlysetting and warn if this setting is enabled.
For compatibility with MySQL 5.7, the tpm command will use the
authentication_stringfield for validating passwords.
For compatibility with MySQL 5.7, the tpm command will now ignore the
The Rhino JS, which is incorporated for use by the filtering and batch loading mechanisms, has been updated to Rhino 1.7R4. This addresses a number of different issues with the embedded library, including a performance issue that could lead to increased latency during filter operations.
The Ruby Net::SSH libraries used by tpm have been updated to the latest version. This addresses issues with SSH and staging based deployments, including KEX algorithm errors.
On some platforms the keytool command could fail to be found, causing an error within the installation when generating certificates.
The tpasswd could create a log file with the wrong permissions.