Right now, I am only using Cloudflare for serving the DNS information for my website. I also want to proxy the requests via Cloudflare (for security reasons).
But when I make the switch, I see a sharp increase in the TTFB of my website from 250 - 400 ms to 600 - 800 ms.
A proxy will naturally always increase latency. There is not much you can do, save for disabling the proxy, which you seem to have done for now.
For me however, there is not much difference whether I access your site directly or via Cloudflare. The site takes initially about two seconds to load, but then loads additional resources and finishes in both cases after about eight seconds. Might be your routing in this case.
Can you post a screenshot of https://cloudflare-test.judge.sh/?
Yes, I think the difference is most probably due to routing as I am in India and all the resources are located in India as well.
I shifted to proxy and tried the tool you suggested, it says - “Likely not a Cloudflare website, or not proxied”, even after waiting for a while and checking the DNS (it is not our server). Can you help me out ?
Also, the TTFB of the website rose to 1200-1300 ms this time.
Yes, your ISP seem to route most Cloudflare addresses to Singapore instead of the Indian locations. Only a few (even among the Enterprise plans) seem to go to India. Thats something that is mostly within your ISP’s control, please see aforementioned article for that.