Cloudflare IP ranges?


#1

Hi folks. I have whitelisted the IP ranges in this page https://www.cloudflare.com/ips/ but I’ve noticed a few 403 for other addresses that seem to belong to Cloudflare according to WHOIS - e.g. 198.41.238.25

Are some of the IPs missing from that page?

Thanks!


#2

They are listed.

Notice the CIDR prefix 198.41.128.0**/17**.

So, 198.41.128.0/17 translates to network mask of 255.255.128.0 with the IP range of 198.41.128.1 to 198.41.255.254.


#3

Doh, yes. But strange IIS returns a 403 for that address as it is not doing the calculations correctly.

I will have another look through the logs now.


#4

IIS should recognize CIDR, or maybe you have to provide them network mask. Take a look at the docs.
I really don’t know about IIS. My first and last deployment with IIS was in 2004. :smiley: