Release Notes for MariaDB MaxScale 6.2.3

Overview

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

MariaDB MaxScale 6.2.3 was released on 2022-03-09. This release is of General Availability (GA) maturity.

Issues Fixed

Can Result in Crashes, Hangs, Stalls

  • When Read/Write Split Router (readwritesplit) is configured with causal_reads=local, server failure can cause MaxScale to crash. (MXS-4005)

  • When the Cache Filter (cache) uses Redis for storage and timeout > 0 is configured on the Redis node, Redis can close MaxScale's idle connections, and MaxScale can crash with a segmentation fault (signal 11) when it tries to clear the cache. (MXS-3954)

Can Result in Unexpected Behavior

  • Query classifier cache does not properly record all used memory which can cause memory usage to exceed configured value of query_classifier_cache_size. (MXS-4008)

  • When Read/Write Split Router (readwritesplit) is configured with causal_reads=local, and a causal read fails due to a timeout or other error, the active operation count is not correctly decremented. (MXS-4007)

  • When the KILL statement is executed, a race condition could sometimes cause the statement to be discarded. (MXS-4004)

  • When the KILL statement is executed and log_info is enabled, no details of the operation are logged. (MXS-4002)

  • Binlog Router (binlogrouter) creates malformed replication events which can cause the binlogfilter to error out if it encounters such an event. (MXS-4000)

  • When a TLS certificate has usage flags via the X509v3 Extended Key Usage extension, MaxScale does not verify that the certificate has the correct usage flags: (MXS-3931)

    • Starting with this release, if a TLS certificate has usage flags via the X509v3 Extended Key Usage extension, MaxScale will check the usage flags and refuse to use a certificate with the wrong usage.

    • A certificate that only has the clientAuth flag can only be used with servers.

    • A certificate that only has the serverAuth flag can only be used with listeners.

    • A certificate that has both the clientAuth and serverAuth flags can be used with servers and listeners.

  • When users_refresh_time > 0 is configured, maxctrl reload service does not bypass the rate limit. (MXS-4038)

  • In the MaxGUI Query Editor, the Don't Limit option has been removed as a max_rows value. (MXS-3957)

  • In the MaxGUI Query Editor, the Y axis dropdown doesn't show accurate table columns. (MXS-4030)

  • When a monitor is stopped, the MaxGUI dashboard doesn't show the monitor. (MXS-4021)

  • Under heavy loads, REST API requests can take too long. (MXS-3808)

  • When the Avro Router (avrorouter) is used, reading an Avro file can fail with Sync marker mismatch. (MXS-3945)

  • When log_info is enabled, some monitor state transitions are not written to the log. (MXS-3979)

  • When MaxScale sends a COM_CHANGE_USER command to the server, MaxScale does not always properly handle the response, which could cause the following warning to be written to the MaxScale log: (MXS-3984)

    warning: (65) [MariaDBProtocol] (SERVICE_NAME); COM_CHANGE_USER from 'USER_NAME' to 'USER_NAME' succeeded on MaxScale yet failed on backends.
    
  • When the Cache Filter (cache) is used and a statement cannot be cached, the following warning could be written to the MaxScale log: (MXS-4035)

    warning: [cache] Invalidation is enabled but the current statement could not be parsed. Consequently, the result cannot be cached.
    
  • When the Cache Filter (cache) uses Redis for storage and timeout > 0 is configured on the Redis node, Redis can close MaxScale's idle connections, which could cause subsequent cache activity to fail and the following error message to be written to the MaxScale log: (MXS-4001)

    error  : [storage_redis] Failed to read reply in the context of MULTI: general error, Server closed the connection
    error  : [storage_redis] Failed when reading response to MULTI: no error, Server closed the connection
    

Platforms

In alignment to the MariaDB Corporation Engineering Policy, MariaDB MaxScale 6.2.3 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 12 (x86_64 / ARM64)

  • SUSE Linux Enterprise Server 15 (x86_64 / ARM64)

  • Ubuntu 18.04 (x86_64 / ARM64)

  • Ubuntu 20.04 (x86_64 / ARM64)