This gives a partial listing of all the sites hosted directly on Hostingraja: https://myip.ms/view/hosts/40988277/hostingraja_org.html
These are the Cloudflare IP range that shouldn't be blocked by my webhost for proper working of my websites via Cloudflare: https://www.cloudflare.com/ips/
My webserver is placed behind Cloudflare for security. This special URL tells from which data center someone is being served: https://ekvastra.in/cdn-cgi/trace
And this link tells, from the same location and connection, what is the POP that the ISP (and Cloudflare) is going to: https://188.8.131.52/cdn-cgi/trace
For emailing pdf functionality I have enabled allow_url_fopen for quiz.ekvastra.in with my hosting provider. This feature cannot be enabled at user level.