MariaDB MaxScale 2.3.1 Release Notes -- 2018-11-20
MariaDB MaxScale 2.3.1 Release Notes -- 2018-11-20
Release 2.3.1 is a Beta release.
This document describes the changes in release 2.3.1, when compared to the previous release in the same series.
For any problems you encounter, please consider submitting a bug report on our Jira.
Changed Features
Unknown global parameters
Unknown global parameters or parameters with invalid values are now treated as errors. If MaxScale refuses to start after upgrading to 2.3.1, check whether it is due to an unknown global parameter.
REST-API
/v1/sessions
The response will, if the feature has been enabled with the
retain_last_statements
parameter, either globally or specifically
for a service, contain information about the last queries executed
by a session.
Binlog Router
Secondary masters can now be specified also when file + position based replication is used. Earlier it was possible only in conjunction with GTID based replication.
mmmon
and ndbclustermon
Both of these modules have been deprecated and will be removed in a future
release. The functionality in mmmon
has been largely obsoleted by the
advancements in mariadbmon
. The ndbclustermon
is largely obsolete due to the
fact that there are virtually no users who use it.
Deprecated features
The following configuration file options have been deprecated and will be removed in 2.4.
Global section
non_blocking_polls
, ignored.poll_sleep
, ignored.thread_stack_size
, ignored.
Services and Monitors
passwd
, replaced withpassword
.
MaxAdmin
MaxAdmin has been deprecated in favor of the REST API and MaxCtrl. It will be removed in a later release.
In addition to this the commands set pollsleep
and set nbpolls
have been
deprecated and will be removed already in 2.4.
MaxInfo
The maxinfo
router has been deprecated and will be removed in a later release.
Debugcli
The debugcli
module has been deprecated and will be removed in 2.4.
New Features
ColumnStore Monitor
The new csmon
monitor can be used to monitor ColumnStore clusters where the
primary UM will be assigned as the master and secondary UMs as slaves. Automatic
detection of the primary UM is supported with ColumnStore versions 1.2.1 and
newer. For older versions the primary UM must be designated with the primary
parameter of the monitor.
Read the csmon documentation for more information on how to use it.
MaxCtrl
There is now a new command classify <statement>
using which it can
be checked if and how MaxScale classifies a specific statement. This
feature can be used for debugging, if there is suspicion that MaxScale
sends a particular statement to the wrong server (e.g. to a slave when it
should be sent to the master).
Services
The global configuration parameter retain_last_statements
can now
also be specified separately for individual services.
Watchdog
If MaxScale is running as a systemd service, the systemd Watchdog can be enabled and MaxScale will behave accordingly. Please see the documentation for more details.
By default the watchdog is disabled.
NOTE: In 2.3.1 there is a deficiency that manifests itself so that if any administrative operation, performed using maxctrl or maxadmin, takes longer that the specified watchdog timeout, then the watchdog will kill and restart MaxScale. Please take that into account before enabling the watchdog.
Miscellaneous
- MXS-2141 Retry read on master when causal_reads timeout is exceeded
- MXS-2122 Immediately close the listening socket when a listener is destroyed
- MXS-2077 Provide more information in list clients output.
- MXS-1976 MaxAdmin Shutting Down A Service should specify / warn that new session requests are neither accepted nor denied.
Bug fixes
- MXS-2147 Luafilter is missing symbols
- MXS-2144 Doing a controlled shutdown doesn't trigger query retrying
- MXS-2142 Default timeout value for causal_reads is excessive
- MXS-2140 Enabling transaction_replay at runtime doesn't enable implicit parameters
- MXS-2139 transaction_replay doesn't implicitly enable master_failure_mode=fail_on_write
- MXS-2136 passwd errors out as a attribute in [monitor] and [service] in maxscale.cnf
- MXS-2121 Listeners defined in the configuration cannot be destroyed
- MXS-2109 query_classifier_cache_size is per thread
- MXS-2107 writeq_high_water doesn't work
- MXS-2100 Unknown global parameters are not detected
- MXS-2098 maintenance_on_low_disk_space does not work
- MXS-2096 SELECT ... INTO OUTFILE is routed to all back end servers
- MXS-2055 Monitor REST-API documentation
- MXS-1978 SELECT INTO OUTFILE is routed to all servers
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 supported the Linux distributions.
Packages can be downloaded here.
Source Code
The source code of MaxScale is tagged at GitHub with a tag, which is identical
with the version of MaxScale. For instance, the tag of version X.Y.Z of MaxScale
is maxscale-X.Y.Z
. Further, the default branch is always the latest GA version
of MaxScale.
The source code is available here.