changing port for vestacp backend will also change port for /phpmyadmin

vim /usr/local/vesta/nginx/conf/nginx.conf
# find this lines
# Vhost
    server {
        listen          8083; <- change new port

:wq # save and quit
# restart vesta
service vesta restart

what you can do is modify the /url/path/to/phpmyadmin

vim /etc/httpd/conf.d/phpMyAdmin.conf

# find those lines
Alias /phpMyAdmin /usr/share/phpMyAdmin
Alias /phpmyadmin /usr/share/phpMyAdmin

# for example you can delete the first line
# and modify the second line:
Alias /top/secret/path/to/phpmyadmin /usr/share/phpMyAdmin

:wq # save and quit

# restart apache
service httpd restart

stay secure!

PS: Bonus question: What html file to modify in order to have a working link from vestacp backend?