Requiring PTR
2008-04-12 07:35:03
Frank Ellermann wrote:
Hector Santos wrote:
[after exploring the wonders of "receiver policy"]
more interesting, is the mixed response codes for the DATA command:
C: DATA
S: 354 START MAIL INPUT, END WITH "." ON A LINE BY ITSELF
S: 421-: (DNS:NR) http://postmaster.info.aol.com/errors/421dnsnr.html
S: 421 SERVICE NOT AVAILABLE
Buggy, isn't it ?
BTW, why does the sender policy of fbgcollection.com talk
about ptr in various ways when that's not supposed to work ?
While I was more concern with timeout issues, the issue
is the same - MIXED reply codes which was "semantically"
possible in 821
What we discussed was one reply with different codes, in
the example 354-... 421-... 421, what you found here is an
unsolicited reply 421 after 354. No problem in 2821bis-09.
Sorry for my false alarm and confusion.
Right, I have no idea what went through my head while I was on GoDaddy
hold, listening to Gigolo music, staring at this log when I decided to
post this PTR issue and also throw in this mixed codes and not
read/comprehend my writing BEFORE clicking "SEND". I did only after I
clicked SEND when I realized I was off base hence the followup correction.
Regarding PTR records, although I knew there were ESPs and other mail
receivers now enforcing it, I always felt it wasn't a big issue for
business accounts. Many systems, and naively believed AOL too, I
believe used services like from MAPS RBL which lookup the zone owner to
determine if this was a home or business tier.
So you didn't see much reports about this and even if it was, the admin
of the system would get a PTR record one way or another.
But in the last two weeks or so, we had several reports. One of them
being my brother, I personally investigated for him. I naturally told
him he needs to contact his ISP (AT&T) for his IP address. But possibly,
his delay in accepting that answer, probably because he didn't know why
A) it had to be done now and never before, and B) it couldn't be
resolved at GoDaddy where he was managing his DNS setup, got me to waste
time to talk to GoDaddy completely forgetting they were not capable of
doing this. John K reminded me the ISP is responsible.
This does raise the question if AOL, who had this policy for a long
time, recently lower the cost of operation by discontinuing using the
fee based MAPS RBL service and now applied the PTR rule across the board
with a general PTR lookup regardless of the IP type. This sounds to me
what has happen because as Vince said, this wasn't an issue before or it
wasn't one that was realized until this week.
It may also raise the question when the "World's largest ESP" and a
growing amount of other ESPs/ISP mail receivers forcing this PTR
record, should be 'Highlighted' in 2821bis.
I mean, there are some who believe the MX is required for security
reasons. Well, why not PTR?
Its stupid I think and x821 always allowed PTR checking as an option,
but it was so unreliable, it wasn't a real issue and hardly used in my
experience.
But I am at a point now where I'm no longer sure what make sense any
more or that it really matter any more. What pisses me off is this new
growing behavior is pushing the support burden on smaller vendors and
people like myself and brother.
I guess there is also some selfishness here because as with most things,
if it doesn't happen to you, if you don't feel it, most people who
careless about it.
--
Sincerely
Hector Santos, CTO
http://www.santronics.com
http://santronics.blogspot.com
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