Release Notes for MariaDB MaxScale 6.3.1


MariaDB MaxScale is an advanced database proxy, firewall, and query router. MaxScale is a component of MariaDB Enterprise.

MariaDB MaxScale 6.3.1 was released on 2022-05-16. This release is of General Availability (GA) maturity.

Notable Changes

  • Improvements to the MaxGUI query editor visualization feature. (MXS-4059)

  • When using maxctrl show sessions or maxctrl list sessions the remote client's port number is now displayed in addition to the remote client's IP address. (MXS-4084)

Issues Fixed

Can Result in a Hang or Crash

  • When the Kafka CDC router (kafkacdc), is being used with a match or exclude statement a crash occurs with an error like: (MXS-4099)

    alert  : MaxScale 6.3.0 received fatal signal 11.
    alert  : Statement currently being classified: none/unknown
  • Using the Avro router (avrorouter) with a SEQUENCE engine table can cause a crash. (MXS-4120)

  • Using a mix of MariaDB 10.2.7 and MariaDB 10.6 back-ends can cause MaxScale to crash. (MXS-4101)

  • Using Node.js and calling the show qc_cache endpoint can cause MaxCtrl to run out of memory. (MXS-4121)

Can Result in Unexpected Behavior

  • When using Read Connection router (readconnroute) configured with two master servers and the first has rank=primary and the second has rank=secondary, router_options=master ignores the rank for first server and chooses the second server. (MXS-4132)

  • When the Read/Write Split router (readwritesplit) is configured with use_sql_variables_in=master, the query is routed normally but the following error is logged: (MXS-4111)

    error  : (1) [readwritesplit] (RW-Split-Router); Can't route COM_QUERY 'SELECT CASE data WHEN 'hello' THEN @var:=2 ELSE @var:=1 END'. SELECT with session data modification is not supported with `use_sql_variables_in=all`.
  • Schema router (schemarouter) does not work with MariaDB Enterprise Server 10.6 unless the ignore_tables_regex is used to exclude it from duplicate checks. The sys schema was added in MariaDB Enterprise Server 10.6 but was not added to the list of database names that are automatically ignored by MaxScale. (MXS-4110)

  • With the MaxScale REST API, the /user/inet endpoint fails schema validation when used with the newest schema for the JSON API specification. (MXS-4109)

  • Executing the SHOW SLAVE STATUS statement via the MaxScale Binlog router (binlogrouter) does not show SSL information. (MXS-4096)

  • Avro router (avrorouter) with CDC to Kafka can fail for some tables. (MXS-4095)

  • Duplicate table errors for tables where the table names are in different cases, for example table.t1 and table.T1 (MXS-4092)

    • Starting with this release, Schema router (schemarouter) compares table and database names case-sensitively. This means that the tables test.t1 and test.T1 are seen as different tables.

    • Prior to this release, Schema router (schemarouter) compares table and database names case-insensitively. This can cause duplicate tables to be found if the server supports case-sensitive table names.

  • The output of the maxctrl list services command displays servers that are in use by that service but does not include services that are added by the targets parameter. (MXS-4127)

  • MaxScale deployments using Redis and the Spyder IDE tool fail with the error (OperationalError: (2013, 'Lost connection to MySQL server during query')) (MXS-4091)

  • In MaxGUI, the parameter's tooltip shows unnecessary attributes. (MXS-4088)

  • The MaxScale REST API is inaccessible after deleting the last REST API user. (MXS-4086)

    • Starting with this release, it is no longer possible to delete all the REST API users. There will always be one user, "the last user", remaining.

    • Prior to this release, it is possible to delete every user of the REST API which would leave the REST API inaccessible.


In alignment to the MariaDB Corporation Engineering Policy, MariaDB MaxScale 6.3.1 is provided for:

  • CentOS 7 (x86_64)

  • Debian 9 (x86_64 / ARM64)

  • Debian 10 (x86_64 / ARM64)

  • Debian 11 (x86_64 / ARM64)

  • Red Hat Enterprise Linux 7 (x86_64)

  • Red Hat Enterprise Linux 8 (x86_64 / ARM64)

  • SUSE Linux Enterprise Server 15 (x86_64 / ARM64)

  • Ubuntu 18.04 (x86_64 / ARM64)

  • Ubuntu 20.04 (x86_64 / ARM64)