What if my server is unavailable to SOME CF IPs?


I see, that CloudFlare has 15 subnets of outgoing IP addresses.
That’s neat, since I can block all but those IPs from accessing my website.

However… What if my operator blocks some addresses - by mistake, wrong information or by some automated attack prevention tools? Will my website become randomly accessible, or will it become unaccessible from some specific world locations?

I tried to figure out, but didn’t find any answer. In particular - what should be done if such situation occurs: is there a possibility to set the list of allowed CF addresses?



I’ve found this is the case. It’s mostly anecdotal evidence, though.

It sounds like you’ve already seen the list, but it’s what your host should allow:

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yes - I’m aware of that that my host should allow those networks - but I was thinking if there are any options to stay online even if this happens. In my life I have seen many strange situations, like whole subnets being blocked because “oh, someone from there tried to hack us from various IPs” or “we are not blocking anything, must be blocked by someone in the middle, maybe a BGP problem”.

I thought that maybe in paid plans there is a possibility of controlling this.

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