TID 10065373 says that you can restrict accounts by subnet by entering
the network address. I wish! Can anybody help with this?
Entering 10.21.16.0, or 10.21.20.0 did not work for IP 10.21.20.129

Network 10.21.16.0 255.255.248.0 i.e. 10.21.16.0 - 10.21.23.255.