Using forwarders results in mail server issue.

[Zelck, Guy]

Hi Marc,

>> Inside our company (eds.com) I manage our groups own little domain
>> (es.be.eds.com) with bind 8.2.3 on Solaris8.
>> We also have sendmail configured for our own domain on a 
>different unix
>> server. This mail server handles mail send to domain 
>es.be.eds.com and uses
>> the smart relay of EDS (defined in sendmail.cf) to deliver 
>mail to other
>> domains. I also have an MX record in our zone file with only 
>our local mail
>> server in it. So far so good, everything works.
>> 
>> Now I wanted to introduce in BIND a forwarder that knows all internet
>> addresses. This forwarder is one of the main EDS internet gateways. 
>> So I changed named.conf to have:
>> options {
>> #
>> # boot file for authoritive master name server for Berkeley.EDU
>> # Note that there should be one primary entry for each SOA record.
>> #
>> #
>>         directory "/var/named";
>>         notify yes;
>>         forward first;
>>         forwarders {
>>                199.42.132.115;
>>        };
>> }; 
>> 
>> For DNS resolving everything works as expected, internet 
>hosts get resolved
>> fine along with the local addresses.
>> The problem is that sendmail doesn't deliver mail for eg 
>guy at es.be.eds.com
>> anymore. It suddenly uses a relay it got, I suppose, from the foreign
>> forwarder i.s.o. relaying the mail itself. I get the feeling 
>that if there
>> would have been an option like 'forwarders last' I wouldn't have this
>> problem. I know however that this option doesn't exist unfortunately.
>> 
>> How can we get round this problem? Anyone knows?
>> 
>> Thanks,
>> Guy.
>
>	You just want to disable forwarding in the internal trees.
>
>	zone "eds.com" {
>		type master;
>		forwarders { /*empty */ };
>		...
>	};
>
This works indeed, thanks.
However I had to solve another weird problem with sendmail.
I had an MX record with hostname mail.es.be.eds.com.
When I sent mail from the nameserver, the mail would sit in the mailqueue
and did not even reach the mailserver. It tried itself to reach a mail
server external to ours in the EDS network. 
The fix was not to use 'mail' as the hostname but sth. else.
Now everything works.

Thanks again,
Guy.