Vlogger from Ubuntu and all its dependencies were already installed during the perfect server setup.
I replaced the old line with the new one in ispconfig.conf and now I get:
DBI connect('database=dbispconfig;host=localhost:3306','ispconfig',...) failed: Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2) at /usr/sbin/vlogger line 507
DBI Error: at /usr/sbin/vlogger line 507, <STDIN> line 60.
piped log program ' /usr/sbin/vlogger -s access.log -t "%Y%m%d-access.log" -d "/etc/vlogger-dbi.conf" /var/log/ispconfig/httpd' failed unexpectedly