MXS-1951: Document SO_REUSEPORT effects

Added a section into limitations and noted the effects in the release
notes.
This commit is contained in:
Markus Mäkelä 2019-03-25 09:36:47 +02:00
parent 66f850d77d
commit 6aa846ebc7
No known key found for this signature in database
GPG Key ID: 72D48FCE664F7B19
2 changed files with 25 additions and 0 deletions

View File

@ -4,6 +4,8 @@ This document lists known issues and limitations in MariaDB MaxScale and its
plugins. Since limitations are related to specific plugins, this document is
divided into several sections.
[TOC]
## Configuration limitations
In versions 2.1.2 and earlier, the configuration files are limited to 1024
@ -14,6 +16,16 @@ In versions 2.2.12 and earlier, the section names in the configuration files
were limited to 49 characters. This limitation was increased to 1023 characters
in MaxScale 2.2.13.
### Multiple MaxScales on same server
Starting with MaxScale 2.4.0, on systems with Linux kernels 3.9 or newer due to
the addition of SO_REUSEPORT support, it is possible for multiple MaxScale
instances to listen on the same network port if the directories used by both
instances are completely separate and there are no conflicts which can cause
unexpected splitting of connections. This will only happen if users explicitly
tell MaxScale to ignore the default directories and will not happen in normal
use.
## Security limitiations
### MariaDB 10.2

View File

@ -19,6 +19,19 @@ configuration files, then MaxScale will not start.
Whitespace in section names that was deprecated in 2.2 will now be
rejected and cause the startup of MaxScale to fail.
### Binding on network ports
MaxScale 2.4.0 will now use the SO_REUSEPORT capability offered by newer kernels
that allows reuse of network listener ports. In practice this means improved
connection creation speed with more dynamic balancing of connections.
As a side-effect of this, it is possible for two MaxScale instances to bind on
the same listener port on systems that have Linux kernels newer than 3.9. This
can only happen if the MaxScale instances use completely different directory
structures (i.e. different `--basedir` arguments). Normal use of MaxScale still
detects multiple MaxScales trying to bind to the same ports. Almost always, this
will not have any negative side-effects.
## Dropped Features
## New Features