Release Notes for MariaDB MaxScale 6.2.2
MariaDB MaxScale is an advanced database proxy, firewall, and query router.
MariaDB MaxScale 6.2.2 was released on 2022-02-14. This release is of General Availability (GA) maturity.
Can Result in Crashes, Hangs, Stalls
When rebalancing is configured by setting
rebalance_periodto a non-zero value, MaxScale can crash. (MXS-3989)
Rebalancing is disabled in this release to avoid crashes.
rebalance_windoware ignored in this release.
BinlogRouteris used, MaxScale can stall and crash. (MXS-3958)
Slow reverse DNS lookups during authentication can cause MaxScale to stall. (MXS-3886)
When database users are defined with a domain name (
'USER'@'HOST.example.com'), MaxScale performs a reverse DNS lookup of the client IP address to see if the IP address resolves to the domain name associated with the user account.
When database users are defined with an IP address (
'USER'@'IP') or a wildcard (
'USER'@'%'), reverse DNS lookups are unnecessary, but MaxScale still performs reverse DNS lookups by default.
This release adds the
skip_name_resolveparameter to disable reverse DNS lookups in environments where they are unnecessary.
skip_name_resolveis set to
true, MaxScale will not perform reverse DNS lookups of client IP addresses.
When MaxScale begins shutting down and receives a REST API request at the same time, MaxScale can hang. (MXS-3865)
MariaDB replica fails due to duplicate
transaction-startrecords in the binlog. (MXS-3953)
transaction-startis immediately written to the binlog and if MaxScale is killed before the full transaction is received, the "transaction-start" will (eventually) be duplicated in the log which could result in the failure of a connected MariaDB replica.
Crash after unexpected result when there is a mismatch between the connection capabilities of the client and the backend server. For example if (MXS-3955):
MaxScale is used with MySQL 5.6
MaxScale is used with MySQL 5.7 that has the query cache enabled
Persistent connections are being used and the clients do not use a uniform set of capabilities, such as using different connectors or connector versions
Can Result in Unexpected Behavior
BinlogRouteris used, replica servers can receive a version string with the
-BinlogRoutersuffix repeated multiple times (MXS-3978)
When a service's filter is altered or removed, MaxScale can change the capabilities of existing sessions using the service. (MXS-3973)
When MariaDB Monitor (
MariaDBMon) encounters a connection error during startup, the connection error is not logged. (MXS-3966)
When transaction replay is enabled,
ReadWriteSplitRouter doesn't detect implicit commits triggered by certain SQL statements, which can cause a transaction containing an implicit commit to be committed a second time during transaction replay. (MXS-3959)
Starting with this release,
ReadWriteSplitRouter detects implicit commits triggered by
START TRANSACTION. Implicit commits triggered by other SQL statements can still be problematic.
When "transaction" is used as an identifier in a statement, such as when querying a table named
transaction, MaxScale's query classifier incorrectly parses "transaction" as a reserved word, which can cause filters to handle the statement incorrectly. (MXS-3949)
In MaxGUI, with
Columnsselected in the dropdown menu in the results pane, toggling between columns in a query result does not toggle the visibility of columns in the result table. (MXS-3948)
In alignment to the MariaDB Corporation Engineering Policy, MariaDB MaxScale 6.2.2 is provided for:
CentOS 7 (x86_
Debian 9 (x86_
Debian 10 (x86_
Debian 11 (x86_
Red Hat Enterprise Linux 7 (x86_
Red Hat Enterprise Linux 8 (x86_
SUSE Linux Enterprise Server 12 (x86_
SUSE Linux Enterprise Server 15 (x86_
Ubuntu 18.04 (x86_
Ubuntu 20.04 (x86_