Cloudflare DNS moving to cloudflare

Hello

I saw the recent implementation of cloudflare DDOS protections (without monthly paying) and I like that, and thinking into moving to them for that:

for other members using it with the cenminmod, would u please:

1-what steps in the settings do u change to move?
2-is it compatible with varnish on the server?
3-is it useful with CDN I alredy use
4-will the free option allowing for premium traffic or that would be slower than the paid monthly subscription?


best.

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