Ok, here's a typical setup (ignoring NS records) that people use for 
hosting domains

Your main zone is

mydomain.com        A         123.456.789.123
www.mydomain.com    CNAME     mydomain.com
mydomain.com        MX        10 mydomain.com

Lets assume you have a full Class C, since it's simpler than classless 
delegation (when you have 8/16/32/64/128 IP addresses)

Then your reverse zone includes:

123.789.456.123.in-addr.arpa  PTR  mydomain.com

So you're typically sending mail with your address ([EMAIL PROTECTED]) via 
your SMTP server at mydomain.com which passes the reverse lookup test.  

Your client at herdomain.com is using virtual hosts on yours server and 
is set up as: 

herdomain.com        A         123.456.789.123
www.herdomain.com    CNAME     herdomain.com
herdomain.com        MX        10 herdomain.com

There can't be a single pointer to two A records, so when 
[EMAIL PROTECTED] sends mail, the reverse lookup points to 
mydomain.com!  This causes the mail to bounce if the reverse lookup test 
is used.



>Very Interesting! I have multiple domains and a single mail server.
>The mail server has its own domain (smtpmirage.net).
>All the hosted domains A records point directly to the IP address. The MX
>record points to mail@<domain>.com (and mail@<domain>.com is an A record
>that points to the IP address).
>Seems to work OK......
>
>Mark Bushaw
>
>----- Original Message ----- 
>From: "Ben Johansen" <[EMAIL PROTECTED]>
>To: <[EMAIL PROTECTED]>
>Sent: Thursday, June 19, 2003 2:36 PM
>Subject: RE: Witango-Talk: including snippets of code [OT]
>
>
>> Interesting
>>
>> Didn't realize that because I have multiple domains on mine.
>>
>> >Anyway, it's just a rant.  I had a server crash on me earlier this year
>>
>> >when it got hijaced by a spammer, and I've spent a lot of hours this
>> year
>> >fighting off spam.  But I still think it's better to allow mail from
>> >senders that don't pass the reverse lookup, and instead rely on black
>> >hole lists at the server, and some simple filters on the mail readers.
>>
>> >Because I don't want to have to tell my clients that we can't receive
>> >mail from them.
>>
>> Considering turning it off.
>>
>> Ben Johansen - http://www.pcforge.com
>> Authorized Witango Reseller http://www.pcforge.com/WitangoGoodies.htm
>> Authorized MDaemon Mail Server Reseller
>> http://www.pcforge.com/AltN.htm
>>
>>
>> -----Original Message-----
>> From: Bill Conlon [mailto:[EMAIL PROTECTED]
>> Sent: Thursday, June 19, 2003 2:11 PM
>> To: [EMAIL PROTECTED]
>> Subject: RE: Witango-Talk: including snippets of code [OT]
>>
>> Off-topic:
>>
>> I would send this directly, but it might bounce.
>>
>> One problem w/ PTR records is they map one-to-one to A records.  But
>> many
>> names (both A and CNAME records) map to one PTR.  Hence if you support
>> many domains with a single mail server, you can't satisfy the reverse
>> lookup condition.
>>
>> Also, you can't always keep PTRs up to date unless you run the reverse
>> zone for your subnet.  Some ISPs will NOT provide classless delegation,
>> so you have to depend on the ISP to maintain your PTRs, leaving you at
>> their mercy -- not a good thing in my opinion.
>>
>> For most of our clients for whom we provide mail, I ask them to use our
>> server for POP, but continue to use their ISP for SMTP.  Some though
>> prefer to use our server for both, and the consequence is that AOL just
>> doesn't get messages from them.
>>
>> Of course AOL's hypocracy is the big story, since they and hotmail have
>> been big spam sources.   And much spam now flows through open relays,
>> which may still have PTR records that match the A record, so what does
>> that do?
>>
>> Anyway, it's just a rant.  I had a server crash on me earlier this year
>> when it got hijaced by a spammer, and I've spent a lot of hours this
>> year
>> fighting off spam.  But I still think it's better to allow mail from
>> senders that don't pass the reverse lookup, and instead rely on black
>> hole lists at the server, and some simple filters on the mail readers.
>>
>> Because I don't want to have to tell my clients that we can't receive
>> mail from them.
>>
>> >Hi,
>> >
>> >Sorry you couldn't connect.
>> >
>> >I went to dnsreport.com and your mail server doesn't reverse DNS
>> >(checkout fail in MX section)
>> >
>> >http://www.dnsreport.com/tools/dnsreport.ch?domain=internetcommercesolu
>> t
>> >ions.net
>> >
>> >In order to curb spam there is a shift in this, AOL has shifted to this
>> >and those who have mail servers that don't have PTR (reverse DNS)
>> cannot
>> >post to AOL. There are a bunch of companies that are following suit
>> >
>> >
>> >Ben Johansen - http://www.pcforge.com
>> >Authorized Witango Reseller http://www.pcforge.com/WitangoGoodies.htm
>> >Authorized MDaemon Mail Server Reseller
>> >http://www.pcforge.com/AltN.htm
>> >
>> >
>> >-----Original Message-----
>> >From: Fogelson, Steve [mailto:[EMAIL PROTECTED]
>> >Sent: Thursday, June 19, 2003 1:26 PM
>> >To: '[EMAIL PROTECTED]'
>> >Subject: RE: Witango-Talk: including snippets of code
>> >
>> >Ben,
>> >
>> >I have had that trouble in the past as well. You might want to check it
>> >out.
>> >I was going to buy a Witango update from you on the day before the
>> price
>> >increases, but couldn't get through you email server.
>> >
>> >Have made the update since.
>> >
>> >Steve Fogelson
>> >
>> >-----Original Message-----
>> >From: John McGowan [mailto:[EMAIL PROTECTED]
>> >Sent: Thursday, June 19, 2003 3:13 PM
>> >To: [EMAIL PROTECTED]
>> >Subject: Re: Witango-Talk: including snippets of code
>> >
>> >
>> >Ben,
>> >
>> >I tried to send this post to you off the list, but your mail server
>> >doesn't seem to be accepting any thing from my mail server.
>> >
>> >Anyway, see my comments below about nested @includes.
>> >
>> >
>> >Ben Johansen wrote:
>> >
>> >>Off List,
>> >>
>> >>Now, I remember (coffee finally kicked in)
>> >>
>> >>The reason your sub-include of the TML works is because TML is one of
>> >>the extensions setup in the web server to tell the web server that
>> >>Witango is responsible to process this file.
>> >>
>> >>
>> >
>> >No,   the @include tag doesn't interact at all with the web server.  It
>> >also doesn't care about file extensions.  When the app server comes
>> >across an @include, it doesn't care what file extension it is... it
>> >simply includes the file and evaluates any meta code it comes across.
>> >
>> >>In the case where an included HTML file calling a SUB-HTML file this
>> is
>> >>not the case. The SUB would not have its metatags processed
>> >>
>> >>
>> >Yes they are... See the enclosed example...  I just tested this out.
>> >
>> >test.taf does an @include of test1.html
>> >
>> >test1.html does an @include of test2.html
>> >test2.html does an @include of test3.html
>> >test3.html executes @currentdate.
>> >
>> >
>> >/John
>> >
>> >_______________________________________________________________________
>> _
>> >TO UNSUBSCRIBE: Go to http://www.witango.com/maillist.taf
>> >_______________________________________________________________________
>> _
>> >TO UNSUBSCRIBE: Go to http://www.witango.com/maillist.taf
>> >
>> >_______________________________________________________________________
>> _
>> >TO UNSUBSCRIBE: Go to http://www.witango.com/maillist.taf
>> >
>>
>>
>> Bill Conlon
>>
>> To the Point
>> 345 California Avenue Suite 2
>> Palo Alto, CA 94306
>>
>> office: 650.327.2175
>> fax:    650.329.8335
>> mobile: 650.906.9929
>> e-mail: mailto:[EMAIL PROTECTED]
>> web:    http://www.tothept.com
>>
>>
>> ________________________________________________________________________
>> TO UNSUBSCRIBE: Go to http://www.witango.com/maillist.taf
>>
>> ________________________________________________________________________
>> TO UNSUBSCRIBE: Go to http://www.witango.com/maillist.taf
>
>________________________________________________________________________
>TO UNSUBSCRIBE: Go to http://www.witango.com/maillist.taf
>


Bill Conlon

To the Point
345 California Avenue Suite 2
Palo Alto, CA 94306

office: 650.327.2175
fax:    650.329.8335
mobile: 650.906.9929
e-mail: mailto:[EMAIL PROTECTED]
web:    http://www.tothept.com


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