On Tue, Jul 31, 2012 at 10:35:35PM -0700, Rick Moen wrote:
Quoting Craig Sanders (cas@taz.net.au):
that's not actually true. you can have as many PTR records as you like for a given rDNS entry.
http://en.wikipedia.org/wiki/Reverse_DNS_lookup#Multiple_pointer_records
Oh very well, yes, you can do that, but That Would Be Extremely Dumb,
actually, no. it would not Be Extremely Dumb. Having multiple PTR records for an IP address is a valid and occasionally useful DNS configuration.
for various fairly obvious reasons
which don't strike me as being particularly obvious.
-- and, more to the immediate point, would completely and automatically bollix any aim to resolve to any specific hostname to make some hypothetical MTA happy.
it's *entirely* the MTA's fault if it freaks out over perfectly valid DNS configuration. configuring an MTA to require matching rDNS resolution is Extremely Dumb in most situations (i.e. where you aren't doing something like restricting incoming smtp connections to a set of known hosts - and there are *much better* methods available for doing that. SSL/TLS client certificate checking for example). craig -- craig sanders <cas@taz.net.au> BOFH excuse #rm268: # modprobe omniscience FATAL: Module omniscience not found.