HOWTO configure an address

Posted on 2008-10-08
Last Modified: 2013-12-09
Hello Experts.

I setup an old server with a LAMP Ubuntu distribution (Hardy Heron) to give it a try and learn.

It works fine (now) and I would like the mail server to be safely configured and respectfull of the anti-spam and whatsoever recommendations. seems happy, exept for this message (I replaced the domain name with a generic one):

"The mail server rejected the email address '' (550 5.1.1 <>: Recipient address rejected: User unknown in local recipient table). It should have accepted the address."
Fine with me! But I do not understand who will use this address, nor how. Therefore, I cannot figure out to which address I should forward the emails of

Can anyone explain the whole picture to me? Thanks a lot in advance.

Question by:Beringhs
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LVL 29

Expert Comment

ID: 22666844
HI yah and

its actually needed for those website who do relay checking Or if you wnat to use some software to check if your mailserver working properly or not, then they sent email email either abuse and webmaster. if you dont have those email address, they will say, mailserver is not accepting email . thats all.

You will see some copany have those email address some comany not. but i guess it good to have.

just create to email account abuse and webmaster. it will stop crying.

Author Comment

ID: 22666868

But then spammers might fill in these accounts easily, to feed up the server, as they are supposed to exist in almost any mail server, no? Should I implement a rule to kill any mail coming in these accounts? Or something?

LVL 29

Expert Comment

ID: 22666910
yes, these 2 accounts exists almost every email server, like one our mailserver has only webmaster but not abuse, another mailserver has both address

if you are not sure, they just dont create, it will not make any difference, as i said, only problem is, if you try to check your mailserver by using dnsstuff or checkdns or like this

they will say
 Probably mail server does not accept mail for and recognizes this as relay attempt.

but if prefer to use atlease one which is webmaster.

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LVL 29

Accepted Solution

fosiul01 earned 250 total points
ID: 22666948
Just read these requiremnt for RFC 2142
its not saying, you will have to have those address, but its good for reports ...

Various Internet documents have specified mailbox names to be used
   when reaching the operators of the new service; for example, [RFC822
   6.3, C.6] requires the presence of a <POSTMASTER@domain> mailbox name
   on all hosts that have an SMTP server.  Other protocols have defacto
   standards for well known mailbox names, such as <USENET@domain> for
   NNTP (see [RFC977]), and <WEBMASTER@domain> for HTTP (see [HTTP]).
   Defacto standards also exist for well known mailbox names which have
   nothing to do with a particular protocol, e.g., <ABUSE@domain> and

   The purpose of this memo is to aggregate and specify the basic set of
   mailbox names which organizations need to support.  Most
   organizations do not need to support the full set of mailbox names
   defined here, since not every organization will implement the all of
   the associated services.  However, if a given service is offerred,
   then the associated mailbox name(es) must be supported, resulting in
   delivery to a recipient appropriate for the referenced service or


   For well known names that are not related to specific protocols, only
   the organization's top level domain name are required to be valid.
   For example, if an Internet service provider's domain name is
   COMPANY.COM, then the <ABUSE@COMPANY.COM> address must be valid and
   supported, even though the customers whose activity generates
   complaints use hosts with more specific domain names like
   SHELL1.COMPANY.COM.  Note, however, that it is valid and encouraged
   to support mailbox names for sub-domains, as appropriate.

   Mailbox names must be recognized independent of character case.  For
   example, POSTMASTER, postmaster, Postmaster, PostMaster, and even
   PoStMaStEr are to be treated the same, with delivery to the same

   Implementations of these well known names need to take account of the
   expectations of the senders who will use them.  Sending back an
   automatic mail acknowledgement is usually helpful (though we suggest
   caution against the possibility of "duelling mail robots" and the
   resulting mail loops).

Author Closing Comment

ID: 31504127
Very good. Thank you. This is what I couldnt find.
LVL 20

Expert Comment

ID: 22669209
WebMaster and Abuse are intended as easy contact points for people to get hold of the owner of the domain.

WebMaster would be used if the site is down or has issues.  Sometimes if I'm browsing and I see a site down I fire off an email to '' with the hope it will help the owner.
90% of them bounce.  This is NOT a requirement.

abuse is intended for people to contact you if they have been getting spam from your domain.  Again - not a requirement (but may be useful for you to spot spammers working on your system)

Assuming you already have incoming spam squashing software like spamassassin then set both these accounts to forward to your main account.  You can always cut them off or raise their spam thresholds if they get too much spam.

Author Comment

ID: 22676063
Thank you.

This confirms the understanding I had with the previous conversation and research: abuse@domain is very useful for system administrators to be warned if their server is misused, but implementing that address for this purpuse makes it easier for spammers to fill the administrator's main address with spam...

Chaque médaille a son revers.

I will dive into spamassassin now.

Thank you for your help.

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