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.
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