15 Oct
2013
15 Oct
'13
4:39 p.m.
Many mail servers require it as a minimum standard for speaking to their MTA.
In case it's not clear, we're talking about DNS and rDNS for random devices that pop up on consumer and other lightly managed networks. Mail servers, like the ones that sent this message to and from nanog, have static IPs, with DNS configured the same way it is for static IPv4. Regards, John Levine, johnl@iecc.com, Primary Perpetrator of "The Internet for Dummies", Please consider the environment before reading this e-mail. http://jl.ly