B.1. Requirements

B.1.1. Operating Systems Support

The following Operating Systems are fully supported for installation of the various Tungsten components and are part of our regular QA testing processes. Other variants of Linux may work at your own risk, but use of them in production should be avoided and any issues that arise may not be supported. Windows/MAC OS is NOT supported, however appropriate Virtual Environments running any of the supported distributions listed would be supported, although only recommended for Development/Testing environments.

Whilst Tungsten Replicator will only work on the operating systems listed, if you choose to run your source/target databases on a different platform, such as Windows or MAC OS, then you would need to confiigure the extractor and appliers as "offboard" services. More information on this deployment model can be found in the Deploymenmt doc pages for Tungsten Replicator

  • Amazon Linux 2

  • CentOS 7

  • RHEL 7

  • RHEL 8.4.0 and deriviates:

    • Rocky Linux

    • Oracle Linux

    • AlmaLinux

  • Debian GNU/Linux 9 (Stretch)

  • Debian GNU/Linux 10 (Buster)

  • Ubuntu 18.04 LTS (Bionic Beaver)

  • Ubuntu 20.04 LTS (Focal Fossa)

  • SUSE Linux Enterprise Server 15

B.1.2. Database Support

Unless stated, MySQL refers to the following variants:

  • MySQL Community Edition
  • MySQL Enterprise Edition
  • Percona MySQL

Table B.1. MySQL/Tungsten Version Support

Database MySQL Version Tungsten Version Notes
MySQL 5.0, 5.1 All Versions up to 6.1.3 Full Support. Newer releases may function with these older MySQL releases at users own risk, any incompatibilities found won't be fixed.
MySQL 5.5, 5.6 All Versions Full Support
MySQL 5.7 5.3.0, 6.0.0 Supported but excludes Geometry, JSON and VIRTUAL Column Types
MySQL 5.7 5.3.1-5.4.1, 6.0.1 onwards Full Support
MySQL 8.0.0-8.0.21 5.4.0-5.4.1, 6.1.0-6.1.3 Supported, but does not support Partitioned Tables or the use of binlog-transaction-compression=ON introduced in 8.0.20
MySQL 8.0.0-8.0.32 6.1.4 onwards Fully Supported.
MariaDB 5.5, 10.0, 10.1 All Versions Full Support
MariaDB 10.2, 10.3 6.1.13-6.1.20 Partial Support. See note below.
MariaDB 10.3 onwards 7.x Full Support

Known Issue affecting use of MySQL 8.0.21

In MySQL release 8.0.21 the behavior of CREATE TABLE ... AS SELECT ... has changed, resulting in the transactions being logged differenly in the binary log. This change in behavior will cause the replicators to fail.

Until a fix is implemented within the replicator, the workaround for this will be to split the action into separate CREATE TABLE ... followed by INSERT INTO ... SELECT FROM... statements.

If this is not possible, then you will need to manually create the table on all nodes, and then skip the resulting error in the replicator, allowing the subsequent loading of the data to continue.

MariaDB 10.3+ Support

Full support for MariaDB version 10.3 has been certified in v7.0.0 onwards of the Tungsten products.

Version 6.1.13 onwards of Tungsten will also work, however should you choose to deploy these versions, you do so at your own risk. There are a number of issues noted below that are all resolved from v7.0.0 onwards, therefore if you choose to use an earlier release, you should do so with the following limitations acknowledged:

  • tungsten_find_orphaned may fail, introducing the risk of data loss (Fixed in v6.1.13 onwards)

  • SSL from Tungsten Components TO the MariaDB is not supported.

  • Geometry data type is not supported.

  • Tungsten backup tools will fail as they rely on xtrabackup, which will not work with newer release of MariaDB.

  • tpm might fail to find correct mysql configuration file. (Fixed in 6.1.13 onwards)

  • MariaDB specific event types trigger lots of warnings in the replicator log file.

B.1.3. RAM Requirements

RAM requirements are dependent on the workload being used and applied, but the following provide some guidance on the basic RAM requirements:

  • Tungsten Replicator requires 2GB of VM space for the Java execution, including the shared libraries, with approximate 1GB of Java VM heapspace. This can be adjusted as required, for example, to handle larger transactions or bigger commit blocks and large packets.

    Performance can be improved within the Tungsten Replicator if there is a 2-3GB available in the OS Page Cache. Replicators work best when pages written to replicator log files remain memory-resident for a period of time, so that there is no file system I/O required to read that data back within the replicator. This is the biggest potential point of contention between replicators and DBMS servers.

B.1.4. Disk Requirements

Disk space usage is based on the space used by the core application, the staging directory used for installation, and the space used for the THL files:

  • The staging directory containing the core installation is approximately 150MB. When performing a staging-directory based installation, this space requirement will be used once. When using a INI-file based deployment, this space will be required on each server. For more information on the different methods, see Section 9.1, “Comparing Staging and INI tpm Methods”.

  • Deployment of a live installation also requires approximately 150MB.

  • The THL files required for installation are based on the size of the binary logs generated by MySQL. THL size is typically twice the size of the binary log. This space will be required on each machine in the cluster. The retention times and rotation of THL data can be controlled, see Section D.1.5, “The thl Directory” for more information, including how to change the retention time and move files during operation.

A dedicated partition for THL and/or Tungsten Software is recommended to ensure that a full disk does not impact your OS or DBMS. Local disk, SAN, iSCSI and AWS EBS are suitable for storing THL. NFS is NOT recommended.

Because the replicator reads and writes information using buffered I/O in a serial fashion, there is no random-access or seeking.

B.1.5. Java Requirements

All components of Tungsten are certified with Java using the following versions:

  • Oracle JRE 8

  • Oracle JRE 11 (From release 6.1.2 only)

  • OpenJDK 8

  • OpenJDK 11 (From release 6.1.2 only)

  • Java 9, 10 and 13 have been tested and validated but certification and support will only cover Long Term releases.


There are a number of known issues in earlier Java revisions that may cause performance degradation, high CPU, and/or component hangs, specifically when SSL is enabled. It is strongly advised that you ensure your Java version is one of the following MINIMUM releases:

  • Oracle JRE 8 Build 261
  • OpenJDK 8 Build 222

All versions from 8u265, excluding version 13 onwards, contain a bug that can trigger unusually high CPU and/or system timeouts and hangs within the SSL protocol. To avoid this, you should add the following entry to the wrapper.conf file for all relevant components. This will be included by default from version 6.1.15 onwards of all Tungsten products.

wrapper.conf can be found in the following path {INSTALLDIR}/tungsten/tungsten-component/conf, for example: /opt/continuent/tungsten/tungsten-manager/conf

wrapper.java.additional.{next available number}=-Djdk.tls.acknowledgeCloseNotify=true

For example:


After editing the file, each component will need restarting


If your original installation was performed with Java 8 installed, and you wish to upgrade to Java 11, you will need to issue tools/tpm update --replace-release on all nodes from within the software staging path.

This is to allow the components to detect the newer Java version and adjust to avoid calls to functions that were deprecated/renamed between version 8 and version 11.

B.1.6. Cloud Deployment Requirements

Cloud deployments require a different set of considerations over and above the general requirements. The following is a guide only, and where specific cloud environment requirements are known, they are explicitly included:

Instance Types/Configuration

Attribute Guidance Amazon Example
Instance Type Instance sizes and types are dependent on the workload, but larger instances are recommended for transactional databases. m4.xlarge or better
Instance Boot Volume Use block, not ephemeral storage. EBS
Instance Deployment Use standard Linux distributions and bases. For ease of deployment and configuration, the use of Ansible, Puppet or other script based solutions could be used. Amazon Linux AMIs

Development/QA nodes should always match the expected production environment.

AWS/EC2 Deployments

  • Use Virtual Private Cloud (VPC) deployments, as these provide consistent IP address support.

  • Multiple EBS-optimized volumes for data, using Provisioned IOPS for the EBS volumes depending on workload:

    Parameter tpm Option tpm Value MySQL my.cnf Option MySQL Value
    / (root)     
    MySQL Data datasource-mysql-data-directory /volumes/mysql/data datadir /volumes/mysql/data
    MySQL Binary Logs datasource-log-directory /volumes/mysql/binlogs log-bin /volumes/mysql/binlogs/mysql-bin
    Transaction History Logs (THL) thl-directory /volumes/mysql/thl   

Recommended Replication Formats

  • MIXED is recommended for MySQL Primary/Replica topologies (e.g., either single clusters or primary/data-recovery setups).

  • ROW is strongly recommended for Composite Active/Active setups. Without ROW, data drift is a possible problem when using MIXED or STATEMENT. Even with ROW there are still cases where drift is possible but the window is far smaller.

  • ROW is required for heterogeneous replication.

B.1.7. Docker Support Policy

B.1.7.1. Overview

Continuent has traditionally had a relaxed policy about Linux platform support for customers using our products.

While it is possible to install and run Continuent Tungsten products (i.e. Clustering/Replicator/etc.) inside Docker containers, there are many reasons why this is not a good idea.

B.1.7.2. Background

As background, every database node in a Tungsten Cluster runs at least three (3) layers or services:

  • MySQL Server (i.e. MySQL Community or Enterprise, MariaDB or Percona Server)

  • Tungsten Manager, which handles health-checking, signaling and failover decisions (Java-based)

  • Tungsten Replicator, which handles the movement of events from the MySQL Primary server binary logs to the Replica databases nodes (Java-based)

Optionally, a fourth service, the Tungsten Connector (Java-based), may be installed as well, and often is.

B.1.7.3. Current State

As such, this means that the Docker container would also need to support these 3 or 4 layers and all the resources needed to run them.

This is not what containers were designed to do. In a proper containerized architecture, each container would contain one single layer of the operation, so there would be 3-4 containers per “node”. This sort of architecture is best managed by some underlying technology like Swarm, Kubernetes, or Mesos.

More reasons to avoid using Docker containers with Continuent Tungsten solutions:

  • Our product is designed to run on a full Linux OS. By design Docker does not have a full init system like SystemD, SysV init, Upstart, etc… This means that if we have a process (Replicator, Manager, Connector, etc…) that process will run as PID 1. If this process dies the container will die. There are some solutions that let a Docker container to have a ‘full init’ system so the container can start more processes like ssh, replicator, manager, … all at once. However this is almost a heavyweight VM kind of behavior, and Docker wasn’t designed this way.

  • Requires a mutable container – to use Tungsten Clustering inside a Docker container, the Docker container must be launched as a mutable Linux instance, which is not the classic, nor proper way to use containers.

  • Our services are not designed as “serverless”. Serverless containers are totally stateless. Tungsten Cluster and Tungsten Replicator do not support this type of operation.

  • Until we make the necessary changes to our software, using Docker as a cluster node results in a minimum 1.2GB docker image.

  • Once Tungsten Cluster and Tungsten Replicator have been refactored using a microservices-based architecture, it will be much easier to scale our solution using containers.

  • A Docker container would need to allow for updates in order for the Tungsten Cluster and Tungsten Replicator software to be re-configured as needed. Otherwise, a new Docker container would need to be launched every time a config change was required.

  • There are known i/o and resource constraints for Docker containers, and therefore must be carefully deployed to avoid those pitfalls.

  • We test on CentOS-derived Linux platforms.

B.1.7.4. Summary

In closing, Continuent’s position on container support is as follows:

  • Unsupported at this time for all products (i.e. Clustering/Replicator/etc.)

  • Use at your own risk