Recently I needed to allow Google thru a firewall and started to track down all of Google’s IPs. GHS or Google Hosted Services is comprised of many IP blocks and they are all used for different purposes. In the list below is only the IPv4 blocks and the ranges.
You can also use the command below to identify all of Google’s mail servers from the SPF record it displays:
nslookup -q=TXT _netblocks.google.com 8.8.8.8 "v=spf1 ip4:216.239.32.0/19 ip4:64.233.160.0/19 ip4:66.249.80.0/20 ip4:72.14.192.0/18 ip4:209.85.128.0/17 ip4:66.102.0.0/20 ip4:74.125.0.0/16 ip4:64.18.0.0/20 ip4:207.126.144.0/20 ip4:173.194.0.0/16 ?all"
Google’s IPv4 CIDR netblock and IP Ranges
64.18.0.0/20 – Range (64.18.0.1 to 64.18.15.254) 64.233.160.0/19 – Range (64.233.160.1 to 64.233.191.254) 66.102.0.0/20 – Range (66.102.0.1 to 66.102.15.254) 66.249.80.0/20 – Range (66.249.80.1 to 66.249.95.254) 72.14.192.0/18 – Range (72.14.192.1 to 72.14.255.254) 74.125.0.0/16 – Range (74.125.0.1 to 74.125.255.254) 173.194.0.0/16 – Range (173.194.0.1 to 173.194.255.254) 207.126.144.0/20 – Range (207.126.144.1 to 207.126.159.254) 209.85.128.0/17 – Range (209.85.128.1 to 209.85.255.254) 216.239.32.0/19 – Range (216.239.32.1 to 216.239.63.254)
If you want to find the current netblocks that Google uses for firewall purposes, just run the nslookup command again. The list above is current as of March 2012.