Virtualmin with MariaDB galera Cluster an MaxScale

Submitted by ghost23 on Wed, 05/23/2018 - 06:55 Pro Licensee

Hi guys,

I got 3 things. We start with the lowest priority ;)

  1. On http://www.webmin.com/cinstall-kvm.html for Debian the connands are wrong. chmod +x cloudmin-gpl-debian-install.sh ./cloudmin-gpl-debian-install.sh

had to be chmod +x cloudmin-kvm-debian-install.sh ./cloudmin-kvm-debian-install.sh

  1. The "Cloudmin GPL Install Script for Xen" fails on a Debian9.4 (net-install) with:

    webmin-security-updates webmin-server-manager webmin-virtual-server-mobile webmin-virtual-server-theme E: There were unauthenticated packages and -y was used without --allow-unauthenticated .. install failed

with the "cloudmin-kvm-debian-install.sh" there is no problem.

and the "cloudmin-debian-install.cgi?serial=xxxxxx" fails with

E: Paket webmin-cloudmin-services kann nicht gefunden werden. .. install failed (can't find package "webmin-cloudmin-services") sorry for german xD

so the way for me ist to install the kvm version and upgrade to cloudmin pro.

Now the highst priority:

  1. How virtualmin creates the mysql users ? I've a galera miradb 10.2 cluster (3 nodes) with a maxscale 2.2 infront of it. So if I cerate a user (from th cloudmin/virtualmin server) with
mysql -u virtualmin -p -h maxscale-ip

Enter password: MariaDB [(none)]> CREATE USER 'virtualmin_test_user'@'%' IDENTIFIED BY 'password';

the user will be synced about all 3 sql hosts as it should be. But if I create a user about " Webmin -> Servers -> MySQL Database Server -> User Permissions" the user will be createt on ge galera master host but not synced to the slaves the same if I create a virtual server with "Virtualmin -> Create Virtual Server -> ... " the users are on the master node bot not on the slaves. So I think it is a issue with the way virtualmin creates th mysql users. BTW of course i'hv added the mysql cluster " Virtualmin -> System Settings -> MySQL Servers"

Status: 
Active

Comments

Submitted by ghost23 on Fri, 05/25/2018 - 02:00 Pro Licensee

Hi @all,

after a little research I found something for this.

http://galeracluster.com/documentation-webpages/userchanges.html

Galera not replicate MyISAM and the mysql.* are MyISAM. Galera will replicate it if they are modified with DDL statements ( https://en.wikipedia.org/wiki/Data_definition_language )

So it seems to me webmin / virtualmin create the sql users with someting like "INSERT INTO mysql.user" is this right? If it's true could it be changed into for example "CREATE USER" or is there a reason to do it like it's done now?

Submitted by JamieCameron on Fri, 05/25/2018 - 19:06

  1. I'll fix that.

  2. So the KVM install works, but the Xen install fails with those package signature errors?

  3. Yes, right now Webmin creates users with the insert into users statement as this is more flexible and less vulnerable to changes in the syntax of the create user command. It's unlikely we would change this in the near term ..

Submitted by ghost23 on Wed, 05/30/2018 - 04:24 Pro Licensee

  1. yes
  2. so virtualmin will not full compatible with a galera cluster except I set "wsrep_replicate_myisam=1" ?

Submitted by JamieCameron on Wed, 05/30/2018 - 22:09

Try re-downloading the installer now - it should fix this issue.