SENDMAIL - Deferred: Name Server: daddy: lookup failure

[josel]

Howdy!

I'm using SCO UNIX 5.0.5 and Sendmail 8.8.8b.

I ran `scoadmin` and generated sendmail.cf. I have
a WIN2000 Server running Mercury SMTP Server.

When I run command

# banner hello |sendmail -v lereboursjose@hotmail.com

I get error

lereboursjose@hotmail.com... Deferred: Name server: daddy: host name lookup failure

If I do

# banner hello | mail lereboursjose@hotmail.com

No error is shown but mail is deferred as it seats in
/usr/spool/mqueue

I set my /etc/resolv.conf to

domain fpgroups.com
nameserver 192.168.1.2
hostresorder local bind

and I have an entry for daddy in my /etc/hosts file. I
can ping daddy just fine.

I wonder, can my SMTP Server be the problem (rejecting)?
In such case, I would expect mail to go through and then
sent back as bounced or something ...

Any help will be truly appreciated.

Regards;

Jose Lerebours


KNOWLEDGE: Something you can give away endlessly and gain more of it in the process! - Jose Lerebours

 

[stanhubble]

Is the W2k smtp server setup as the "smarthost" when you did the mkdev cf?

Is the W2K smtp server setup to allow relaying?

 

[thqt07]

Jose,

I am running RedHat 7.2 sendmail with a Win2000 SMTP smarthost and I get the same error. When I look at the mailq I see..

(Deferred: Name server: lobster: host name lookup failure)

after just about everything in there.

Like you I can resolve the smarthost name and ping it. I'm guessing it's something to do with the reverse lookup of the address of the smarthost failing??? Did you ever manage to overcome your problem?

Thanks.

Mike

 

[Annihilannic]

In both cases, do these hostnames look up correctly in DNS, both from the SCO server and the Windows 2000 mail server?

Annihilannic.

 

[josel]

thqt07,

No, I never did. I shut project down and have not gone back to it; too busy with other easier things

Annihilannic,

I am not exactly sure of what you're asking. My /etc/resolf.conf and /etc/hosts files are set with proper server names and IPs. Both servers reach one another via ftp and/or telnet, as well as, PING (name and IP).

One of the suggestions I got was to make sure my SMTP server was set to accept relay from my UNIX server which, I believe to be a reasonable thing to do I never got to check this as I was totally thrown off track.

Thanks;


Jose Lerebours

KNOWLEDGE: Something you can give away endlessly and gain more of it in the process! - Jose Lerebours

 

[Annihilannic]

I meant to type nslookup daddy on both systems and make sure it returned a response.

Annihilannic.

 

[thqt07]

Annihilannic,

Both systems use our local caching DNS proxy server, so both can 'NSLOOKUP' each other and can ping etc. The SMTP software itself uses a different, external DNS server for its MX lookups and wouldn't be able to find the names or addresses (because they are 172.16.x.x and unregistered names). The SMTP server does relay mail for other internal systems - in fact there is a piece of software on the Linux host that sends mail "directly" without using sendmail (but still via the SMTP server) and that works fine. My suspicion is that it is something along the lines of the Linux sendmail trying to lookup the name of the smarthost and then match that against a reverse lookup of the address and it failing. But honestly, within my network I'm not really too worried about that kind of paranoia.

Thanks for your help...

Mike

 

[Annihilannic]

There will almost certainly be a way to disable that behaviour, however you may have more luck asking in the sendmail forum.

Annihilannic.

 

[thqt07]

Annihilannic/Jose,

I fixed it. Sendmail was trying to find an MX record for the name or address of the server I specified as the smarthost. To stop it doing that you can just put square brackets [] around the name or address when you enter it.

Regards,
Mike