Google App Engine - list of IP addresses?

Question

I know that Google App Engine does not support an application having a static IP address, but I'd like to know if there is a list or range of IP addresses that an app could potentially have? I'd like to use that list as a whitelist of IP addresses for another application deployed elsewhere.

Answer 1

In addition to the other answers, GAE premier support directed me to this name, esp as the source IP address for URLFetch calls:

$ dig -t txt _cloud-netblocks.googleusercontent.com

which answers:

include:_cloud-netblocks1.googleusercontent.com
include:_cloud-netblocks2.googleusercontent.com
include:_cloud-netblocks3.googleusercontent.com

if you then query those, you get this list of ranges (as of 2014-06-26):

8.34.208.0/20
8.35.192.0/21
8.35.200.0/23
23.236.48.0/20
23.251.128.0/19
107.167.160.0/19
107.178.192.0/18
108.170.192.0/20
108.170.208.0/21
108.170.216.0/22
108.170.220.0/23
108.170.222.0/24
108.59.80.0/20
130.211.4.0/22
146.148.16.0/20
146.148.2.0/23
146.148.32.0/19
146.148.4.0/22
146.148.64.0/18
146.148.8.0/21
162.216.148.0/22
162.222.176.0/21
173.255.112.0/20
192.158.28.0/22
199.192.112.0/22
199.223.232.0/22
199.223.236.0/23