I am using standard install.
Referenced How to Install Discourse on Ubuntu 20.04 - Complete Guide | Vultr Docs.
I can not use Mysql on docker installation. I installed MariaDB on discourse docker image.
root@localhost-app:/var/www/discourse# service mysql start
mysql: unrecognized service
root@localhost-app:/var/www/discourse#
So I made mysql docker image and uploaded my vBulletine database there. mysql docker image ip address is 172.17.0.5
Thank you.