I have been away and had very limited access to the internet hence I couldn’t reply.
This is the manual I used to build my nextcloud
However, I skipped the database part since I have already installed and clustered the MYSQL database.
I believe that since the database cluster is working very well the next step in my lap work is to install just one server of the nextcloud then connect to any of the database.
Once that is achieve then the next step which is pretty simple to to build a second nextlcoud server and cluster it using HAproxy.
At the moment when I run this command to finish the installation
sudo -u www-data php occ maintenance:install --database “mysql” --database-name “nextcloud” --database-user “nextcloud” --database-pass “YOURdbPASSWORD” --admin-user “ncadmin” --admin-pass “YOURadminPASSWORD”