Release Notes for MariaDB MaxScale 2.5.1


MariaDB MaxScale is an advanced database proxy, firewall, and query router.

MariaDB MaxScale 2.5.1 was released on 2020-07-16. This release is of General Availability (GA) maturity.

New Features

  • MaxCtrl sorts attribute lists in alphabetical order. (MXS-3015)

  • Added the gtid parameter for the Kafka CDC Router. (MXS-3052)

  • MaxGUI added, a browser-based configuration and management tool for MaxScale, based on MaxCtrl.

  • Cache supports cache entry invalidation.

  • Cache supports memcached and Redis storage modules, which allow sharing caches between MaxScale instances.

  • Cache supports user-specific caching.

  • Support added for Mirror Router.

  • Support added for KafkaCDC module to replicate changes from the Primary Server to a Kafka broker formatted as JSON objects.

  • MaxScale can perform load re-balancing, moving sessions from one thread to another so that all threads are evenly utilized.

  • ColumnStore monitor capable of monitoring MariaDB ColumnStore 1.0, 1.2, and 1.5. Able to perform some cluster management operations on ColumnStore 1.5.

  • MaxCtrl --timeout option can be specified using duration suffixes.

  • targets parameter added to services.

  • MariaDB connection attributes forwarded to back-end Servers.

  • MariaDB Monitor adds master_conditions and slave_conditions to replace deprecated parameters.

  • MariaDB Monitor supports cooperative monitoring.

  • Listener configuration support the use of multiple authenticators.

  • Support added for connection_init_sql_file parameter.

  • The PAM Authenticator supports the mysql_clear_password client authentication plugin.

  • Support added for peer hostname verification in TLS connections.

  • Support added for certificate revocation lists on TLS connections.

  • Read/Write Splitter causal reads supports a global mode, which uses the latest known Global Transaction ID and waits for a Replica Server to replicate.

  • Read/Write Splitter causal reads supports a fast mode, which uses the latest known Global Transaction ID and routes queries to the Primary Server if no up-to-date Replica is found.

  • Schema Router supports configuration of multiple servers that contain the same database or table.

  • Schema Router no longer requires that client credentials exist on all Servers used by the service.

  • REST API supports token authentication via JWT.

  • REST API supports sparse field-sets to reduce network overhead for requests.

  • REST API supports result filtering to retrieve a subset of a resource collection.

  • REST API resources use SHA1 of returned result as the object ETag.

  • REST API module parameter types described for the server and core MaxScale objects.

  • REST API separates listener resources from services.

Notable Changes

  • Network throttling enabled by default.

  • MaxScale treats server objects with duplicate network details (address and port) as a configuration error. There should be only one server object for each actual Server.

  • Server configuration is evaluated for unknown parameters, raising a configuration error.

  • Servers without monitors start in the Down state instead of the Running state, requiring you to manually set their state..

  • Read/Write Splitter connection_keepalive parameter is a core MaxScale feature, available to all routers.

  • Default for auth_connect_timeout parameter changed from 3 to 10 seconds.

  • MariaDB Monitor no longer permits setting the Primary Server to maintenance or draining mode. You must perform a switchover first.

  • Password encryption updated to be more secure. Recommended that users generate a new encryption key and re-encrypt their passwords using MaxKeys and MaxPasswd.

  • Updates to authentication modules.

  • REST API treats listeners as separate resources from services. Previous listener entry point is deprecated and its use discouraged.

Deprecated Features

  • Deprecated utility MaxAdmin removed. No longer possible to enable/disable Unix users as MaxScale administrators.

  • MaxInfo Router removed.

  • httpd protocol removed.

  • The auth_read_timeout parameter deprecated and ignored.

  • The auth_write_timeout parameter deprecated and ignored.

  • MariaDB Monitor detect_stale_master deprecated, but still usable. Will be removed in later release.

  • MariaDB Monitor detect_standalone_master deprecated, but still usable. Will be removed in later release.

  • MariaDB Monitor detect_stale_slave deprecated, but still usable. Will be removed in later release.

  • Deprecated non_block_pools parameter removed.

  • Deprecated poll_sleep parameter removed.

  • Deprecated log_trace parameter removed.

  • Deprecated log_messages parameter removed.

  • Server protocol parameter deprecated and ignored.

  • Server authenticator parameter deprecated and ignored.

  • Read/Write Splitter max_slave_connections parameter deprecated.


In alignment to the MariaDB Corporation Engineering Policy, MariaDB MaxScale 2.5.1 is provided for:

  • CentOS 7

  • Debian 9

  • Debian 10

  • Red Hat Enterprise Linux 7

  • Red Hat Enterprise Linux 8

  • SUSE Linux Enterprise Server 12

  • SUSE Linux Enterprise Server 15

  • Ubuntu 18.04

  • Ubuntu 20.04