[Mimedefang] Deadline for SPF records *long w/morbid horoscope*

[WBrown at e1b.org]

mimedefang-bounces at lists.roaringpenguin.com wrote on 08/12/2004 04:20:31 
AM:

> And what do you think the command ETRN is for? One could give these 
hosts
> a lower MX, but on the other hand, if they're almost never online you'd 
have
> to wonder if thats a good thing. 

ETRN requires the queueing MX to be able to resolve the requsting host. 
ETRN only tells the server that it should process and deliver any mail 
mail destined to the requesting server via a new connection.  It does not 
simply reverse the direction of mail flow over the exisiting connection. 
TURN used to do that, but it was very insecure having no validation for 
who was asking for the email.

You still need a lower preference MX, if only on an internal DNS zone, to 
deliver the mail after ETRN.

> Dont forget, the internet is older than the spam problem. Im not saying 
these
> kinds of setups cant be changed, im saying they're not trivial to 
change.
> This discussion started with implementing SPF, and for an ISP 
implementing
> SPF has a lot of problems. Not unsolvable, but it wont be pretty. 

Yep, and it's a pain in the a$$ to replace the door on your house, but if 
it keeps the unwated (cold air,burglars) out, it might be worth the 
cost/effort.