Bumped by Community user
    Bumped by Community user
    Tweeted twitter.com/StackDBAs/status/1106706718946480132
    Bumped by Community user
2 Added the tags of (a) the database management system of relevance, (b) the storage engine of at issue, and (c) the OS of use.
| link
source | link

How to change MySQL InnoDB cluster from single primary mode to multi primary mode?

My goal is to setup, in a lab environment, a MySQL InnoDB cluster in multi-primary mode.

I have read much, but I cannot get this setup to work.

Ubuntu 16.04.3 server LTS x 3 SQL0 - SQL2

Ubuntu 16.04.3 server LTS x 2 REP0 - REP1

All server instances are in Virtual machine except REP0 is on bare metal and REP1 is off line.

Installed MySQL server 8.0 from Oracle APT repo using mysql-apt-config_0.8.10-1_all.deb.

These servers have been up and down with many config changes trying to find a setup that works.

Set MySQL server 8.0 with Legacy Authentication Method on all boxes.

My current /etc/mysql/my.cnf is based on Justin Ellingwood @ DigitalOcean.

This is /etc/mysql/my.cnf from SQL0. This machine was at one time the primary in a single-primary setup that did not work correctly.

The other /etc/mysql/my.cnf file are very similar to this one with the # Host specific replication configuration section changed.

The error I am trying to resolve now is from /var/log/mysql/error.log.

[ERROR] Plugin group_replication reported: 'It is not allowed to run single primary mode with 'enforce_update_everywhere_checks' enabled.'

Yes I do have these set in my.cnf because I want multi-primary mode. I do not want to run in single-primary mode.

loose-group_replication_single_primary_mode = OFF
loose-group_replication_enforce_update_everywhere_checks = ON

Where, How, What else do I need to change for these to be in multi-primary mode and not error out?