MariaDB MaxScale 2.0.1 Release Notes

Release 2.0.1 is a GA release.

This document describes the changes in release 2.0.1, when compared to release 2.0.0.

If you are upgrading from 1.4.3, please also read the release notes of 2.0.0.

For any problems you encounter, please consider submitting a bug report at Jira.

Changed default values

strip_db_esc

The service parameter strip_db_esc now defaults to true.

detect_stale_master

The stale master detection feature is now enabled by default.

Updated Features

Starting MariaDB MaxScale

There is now a new command line parameter --basedir=PATH that will cause all directory paths and the location of the configuration file to be defined relative to that path.

For instance, invoking MariaDB MaxScale like

$ maxscale --basedir=/path/maxscale

has the same effect as invoking MariaDB MaxScale like

$ maxscale --config=/path/maxscale/etc/maxscale.cnf
           --configdir=/path/maxscale/etc
           --logdir=/path/maxscale/var/log/maxscale
           --cachhedir=/path/maxscale/var/cache/maxscale
           --libdir=/path/maxscale/lib/maxscale
           --datadir=/path/maxscale/var/lib/maxscale
           --execdir=/path/maxscale/bin
           --language=/path/maxscale/var/lib/maxscale
           --piddir=/path/maxscale/var/run/maxscale

Password parameter

In the configuration entry for a service or monitor, the value of the password to be used can now be specified using password in addition to passwd. The use of the latter will be deprecated and removed in later releases of MaxScale.

[SomeService]
...
password=mypasswd

Routing hint priority change

Routing hints now have the highest priority when a routing decision is made. If there is a conflict between the original routing decision made by the readwritesplit and the routing hint attached to the query, the routing hint takes higher priority.

What this change means is that, if a query would normally be routed to the master but the routing hint instructs the router to route it to the slave, it would be routed to the slave.

WARNING: This change can alter the way some statements are routed and could possibly cause data loss, corruption or inconsisteny. Please consult the Hint Syntax and ReadWriteSplit documentation before using routing hints.

MaxAdmin Usage

In 2.0.0 (Beta), the authentication mechanism of MaxAdmin was completely changed, so that MaxAdmin could only connect to MaxScale using a Unix domain socket, thus only when run on the same host, and authorization was based on the Unix identity. Remote access was no longer supported.

To the user this was visible so that while you in 1.4.3 had to provide a password when starting maxadmin and when adding a user

user@host $ maxadmin -p password
MaxAdmin> add user john johns-password

in 2.0.0 (Beta), where only Unix domain sockets could be used, you did not have to provide a password neither when starting maxadmin, nor when adding users

user@host $ maxadmin
MaxAdmin> add user john

as the MaxScale user corresponded to a Unix user, provided the Linux user had been added as a user of MaxScale.

In 2.0.1 (GA) this has been changed so that the 1.4.3 behaviour is intact but deprecated, and the 2.0.0 (Beta) behaviour is exposed using a new set of commands:

MaxAdmin> enable account alice
MaxAdmin> disable account alice

Note that the way you need to invoke maxadmin depends upon how MariaDB MaxScale has been configued.

Please consult MaxAdmin documentation for more details.

Bug fixes

Here is a list of bugs fixed since the release of MaxScale 2.0.0.

• MXS-860: I want to access the web site if master server is down
• MXS-870: Assertion of Buffer Overflow
• MXS-845: "Server down" event is re-triggered after maintenance mode is repeated
• MXS-836: "Failed to start all MaxScale services" without retrying
• MXS-835: Please reinstate remote access to maxscaled protocol
• MXS-773: 100% CPU on idle MaxScale with MaxInfo
• MXS-812: Number of conns not matching number of operations
• MXS-856: If config file cannot be accessed and creation of log file fails, MaxScale crashes with SIGSEGV
• MXS-829: When the config file isn't readable or doesn't exist, maxscale silently ends

Known Issues and Limitations

There are some limitations and known issues within this version of MaxScale. For more information, please refer to the Limitations document.

Packaging

RPM and Debian packages are provided for the Linux distributions supported by MariaDB Enterprise.

Packages can be downloaded here.

Source Code

The source code of MaxScale is tagged at GitHub with a tag, which is derived from the version of MaxScale. For instance, the tag of version X.Y.Z of MaxScale is maxscale-X.Y.Z.

The source code is available here.