From: "John Levine" <johnl@iecc.com>
To: nanog@nanog.org
Sent: Sunday, December 3, 2023 12:48:11 PM
Subject: What are these Google IPs hammering on my DNS server?

At contacts.abuse.net, I have a little stunt DNS server that provides domain contact info, e.g.:

$ host -t txt comcast.net.contacts.abuse.net
comcast.net.contacts.abuse.net descriptive text "abuse@comcast.net"

$ host -t hinfo comcast.net.contacts.abuse.net
comcast.net.contacts.abuse.net host information "lookup" "comcast.net"

Every once in a while someone decides to look up every domain in the
world and DoS'es it until I update my packet filters. This week it's
been this set of IPs that belong to Google. I don't think they're
8.8.8.8. Any idea what they are? Random Google Cloud customers? A
secret DNS mapping project?

 172.253.1.133
 172.253.206.36
 172.253.1.130
 172.253.206.37
 172.253.13.196
 172.253.255.36
 172.253.13.197
 172.253.1.131
 172.253.255.35
 172.253.255.37
 172.253.1.132
 172.253.13.193
 172.253.1.129
 172.253.255.33
 172.253.206.35
 172.253.255.34
 172.253.206.33
 172.253.206.34
 172.253.13.194
 172.253.13.195
 172.71.125.63
 172.71.117.60
 172.71.133.51

R's,
John