//etc/httpd/conf/httpd.conf

UseCanonicalName on

NameVirtualHost *:80



<VirtualHost *:80>
DocumentRoot /var/www/joymaininc
ServerName www.1v1.com
ServerAlias joymaininc.com *.joymaininc.com
</VirtualHost>
<VirtualHost *:80>
DocumentRoot /var/www/iamtraining
ServerName www.1v1.com
ServerAlias iamtraining.com *.iamtraining.com
</VirtualHost>
<VirtualHost *:80>
DocumentRoot /var/www/1v1
ServerName www.1v1.com
ServerAlias 1v1.com *.1v1.com
</VirtualHost>

Folder Layout

DNS configuration

joymaininc.com zone

191.121.13.5 A joymaininc.com
191.121.13.5 A mail.joymaininc.com
191.121.13.5 CName www.joymaininc.com

1v1.com zone

191.121.13.5 A 1v1.com
191.121.13.5 A mail.1v1.com
191.121.13.5 CName www.1v1.com

iamtraining.com zone

191.121.13.5 A iamtraining.com
191.121.13.5 A mail.iamtraining.com
191.121.13.5 CName www.iamtraining.com

If you type http://joymainining.com/job, the browser will show https://www.1v1.com/job/. ---->self-referencing redirect

If you type http://joymaininc.com, the browser shows http://joymaininc.com/

Conclusion

The sub-directory is a must for the self-referencing redirect URI to work.

The three directives (ServerName,UseCanonicalName, and ServerAlias) work together.

http://joymaininc.com/job

The ServerAlias joymaininc.com identifies that the ServerName www.1v1.com will be used.

"UseCanonicalName on" informs apache to form a new name http://www.1v1.com/job/ and send it to client browser.