It is possible to have more than one website being hosted from one web server configured with LAMP. Basically name based virtual host is used to host multiple websites in httpd. If you want a particular website to be displayed when server is browsed via IP, than the site must be listed as a default virtual host. First determine which of the website is being listed as default virtual host. You can list the virtual host as
[root@yourwebserver ~] # apachectl -t -D DUMP_VHOSTS
Above command will give you idea about which website will be displayed as default. Now, just make some changes with your httpd.conf file. Considering /etc/httd/conf/httpd.conf as your configuration file
[root@yourwebserver ~] # vi /etc/httpd/conf/httpd.conf
Add default virtual host line in httpd.conf
# Add other required directives and configuration of virtual host.
Make it sure to add default virtual host at the of virtual host config. If you are including conf files from /etc/httpd/conf.d/ then move line
from httpd.conf to the end or after the default virtual host configuration.