>> AFAIK all mailserver are required to have an A record,
>> they are also required to have an RDNS matching "this" A record.
>> This A record then becomes one of the possible domains to reach the mailserver,
>> which RFC 822 requires to have a postmaster@domain (domain being RDNS).
>
> Where do you see this "domain being RDNS" part in the text below?
ANY hostname is in its strictes interpretation is a domain!
The assumption that a mailserver with hostname frog.domain.com
has only one domain for a postmaster -> [EMAIL PROTECTED] ,
will not work if [EMAIL PROTECTED] goes to mail.domain.com
and frog.domain.com only serves mail for frog.net and frog.com
> AFAIK, there's no requirement in the RFC that a mailserver
> accepts mail for anyone or from anyone.
Saying that the localpart postmaster should allways be acceptet,
CAN be interpreted as a mailserver should accept postmaster@*.
This however is not how I have interpreted this RFC!
>> [822 snip]
>> This standard specifies a single, reserved mailbox address
>> (local-part) which is to be valid at each site. Mail sent to
>> that address is to be routed to a person responsible for the
>> site's mail system or to a person with responsibility for general
>> site operation. The name of the reserved local-part address is:
>>
>> Postmaster
> Yes, local part. It's valid on my site, too, if you get the "domain" right.
How can people GUESS your domain ???
As written above with frog.net and frog.com, how do you guess that
frog.domain.com only has [EMAIL PROTECTED] or [EMAIL PROTECTED] ?
> You know, my machine has several interfaces;
> DNS of some of them is controlled by my ISP (because the IP is in their netblock).
> There's no way for me to set up my mailserver to have a name of each interface in
>its control/locals,
> and check daily whether the ISP didn't change the reverse zone.
This seems like a weak excuse, all your interfaces should have matching RDNS
to their main A records and it's sufficient to set this up once!
Instance like this with several customers with different interfaces
where the customers have their own domain and want their "own" mailserver address,
to make it look like it's their private server or any other reason,
should have RDNS that leads to a postmaster@RDNS .
mail.cust1.net has IP 127.1.0.1, then RDNS should be mail.cust1.net.
the control/locals and control/rcpthosts should contain mail.cust1.net
and rcpthosts should contain any other domain they have set up MX for.
same for mail.cust2.net IP 127.1.0.2 and mail.cust3.net IP 127.1.0.3,
should both have RDNS that matches their main A record.
The third party recipient will not SEE any other domain when 127.1.0.X
connect to his server to send E-Mail, than sender address and this is
not enough to identify a postmaster address.
For argument sake the users can CHOOSE their own sender address and relay
throug their "own" server since relay control is usually IP based.
If any @cust1.net also had an another account he was using it when
sitting at work, or whereever he could relay trought mail.cust1.net,
the recipient would see this address as [EMAIL PROTECTED] .
If this was ABUSE, SPAM or technical problems with this relay,
there is noway [EMAIL PROTECTED] would lead me to
[EMAIL PROTECTED] and the ONLY LOGICAL option would be
[EMAIL PROTECTED] since I only know the IP of the relay!
>> so that "Postmaster@domain" is required to be valid.
>
> I still fail to see "domain must be any RDNS for your computer you can think of".
If your mailservers hostname is mail.antek.cz then mail.antek.cz is also an domain,
then [EMAIL PROTECTED] is an required RFC 822 postmaster address.
>> There are surely more ways to get mail to these admins / postmasters,
>> but telnet to port 25 and manually dropping a "rcpt to: <postmaster>"
>> is far to much to ask from a normal person trying to contact a
>> postmaster.
>
> ORBS tester (notifier) is far from being "normal person". After all, a
> normal person wouldn't know how to set up and run such a service.
> Or doesn't ORBS know either?
They postmaster described in RFC822 is for all user, not ORBS only.
ORBS only have the IP address of the mailserver,
as per RFC822 postmaster@RDNS/IP should be enough.
MVH André Paulsberg IDG New Media Support
