Bug #90553 group replication installation docs lead to errors in the logs
Submitted: 21 Apr 2018 10:46 Modified: 11 Jul 2019 7:55
Reporter: Giuseppe Maxia (OCA) Email Updates:
Status: Closed Impact on me:
Category:MySQL Server: Documentation Severity:S3 (Non-critical)
Version:8.0.11 OS:Any
Assigned to: CPU Architecture:Any

[21 Apr 2018 10:46] Giuseppe Maxia
The instructions to run group replication oddly use a same-host setup. 

In addition to failing to properly tell users about how to deploy group replication instances, this choice leads to at least one bad side effect.

One of the nodes will manage to get the X Plugin running (active by default in 8.0.11), but the others will fail. While the server will start, the error log reports:

2018-04-21T10:39:17.577113Z 0 [ERROR] [MY-011292] [Server] Plugin mysqlx reported: 'Preparation of I/O interfaces failed, X Protocol won't be accessible'
2018-04-21T10:39:17.577138Z 0 [ERROR] [MY-011300] [Server] Plugin mysqlx reported: 'Setup of TCP (bind-address:'*', port:33060) failed, `bind()` failed with error: Address already in use (48). Do you already have another mysqld server running with Mysqlx ?'
2018-04-21T10:39:17.577162Z 0 [ERROR] [MY-011300] [Server] Plugin mysqlx reported: 'Setup of UNIX socket (/tmp/mysqlx.sock) failed, another process with PID 89057 is using UNIX socket file'

Notice: do not use dbdeployer (https://www.dbdeployer.com)  to verify this bug, because it deals with this issue transparently, by assigning a distinct port and socket to each instance.

How to repeat:
follow the instructions in the manual, without giving any options about mysqlx port and socket.

Suggested fix:
Quick fix: 
add mysqlx-port and mysql-socket to the servers setup.

Better fix:
change the documentation to use servers in separate hosts, as it should be.
[21 Apr 2018 19:15] MySQL Verification Team
Thank you for the bug report.
[11 Sep 2018 19:57] Warren Prince
So where is a good set of instructions to follow?
[11 Jul 2019 7:55] David Moss
Posted by developer:
Thanks for your feedback. The docs have be reworked to show how to use multiple hosts as the default, and an additional section which covers the rarer case of installing locally has been added. Online after the next release.