Unknown User Error when using Sendmail

[Jeff Paciolla_1]

I have scoured the forum for hints and have tried just about every thing I can think of. I have added the DS, and the DM entry in sendmail.cf. I have created the nsswitch.conf file, I have added the exchange server in my host file.

Here is my problem: When I try to send an email from my HP-UX 11.00 box to an internet email address (say a pager, pin#@airmessage.net) I get an error telling me that the user is unknown (below is a copy of the error in the mail file). The box I am using as my relay is an exchange server.

example of error:

----- The following addresses had permanent fatal errors -----
8773443591@airmessage.net

----- Transcript of session follows -----
... while talking to dallasmail:
>>> RCPT To:<8773443591@airmessage.net>
<<< 550 5.7.1 Unable to relay for 8773443591@airmessage.net
550 8773443591@airmessage.net... User unknown

--MAA16178.1018973623/pikachu.acs-inc.com
Content-Type: message/delivery-status

Reporting-MTA: dns; pikachu.acs-inc.com
Arrival-Date: Tue, 16 Apr 2002 12:13:42 -0400 (EDT)

Final-Recipient: RFC822; 8773443591@airmessage.net
Action: failed
Status: 5.1.1
Remote-MTA: DNS; dallasmail
Diagnostic-Code: SMTP; 550 5.7.1 Unable to relay for 8773443591@airmessage.net
Last-Attempt-Date: Tue, 16 Apr 2002 12:13:43 -0400 (EDT)

--MAA16178.1018973623/pikachu.acs-inc.com
Content-Type: message/rfc822

Return-Path:
Received: (from root@localhost)
by pikachu.acs-inc.com (8.8.6 (PHNE_17190)/8.8.6) id MAA16176;
Tue, 16 Apr 2002 12:13:42 -0400 (EDT)
Date: Tue, 16 Apr 2002 12:13:42 -0400 (EDT)
From: root
Message-Id: <200204161613.MAA16176@pikachu.acs-inc.com>
To: 8773443591@airmessage.net, jeff.paciolla@acs-inc.com
Subject: Test From Pikachu
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit

end of example

All help is greatly appreciated
Thanks
Jeff

[someone_4]

Hello
what do the following do?

sendmail -bv pin#@airmessage.net

try differernt users @ airmessage.net and emails that you know for a fact work aol.com yahoo.com.

nslookup airmessage.net
and do the nslookup for aol.com yahoo.com hotmail.com

richard

[Clemens van Everdingen]

Hi,

Let us know what is in your /etc/sendmail.cw file.

All forms of name resolving should be in there.

like:
localhost
sultan
sultan.domain.com
sultan.

C.

[Jeff Paciolla_1]

Richard -
Here are the responses from your two questions:

#sendmail -bv 8773443591@airmessage.net

8773443591@airmessage.net... deliverable: mailer relay, host dallasmail, user 8773443591@airmessage.
net

#nslookup airmessage.net

Using /etc/hosts on: pikachu

looking up FILES
*** No address information is available for "airmessage.net"

Thanks
Jeff

[Jeff Paciolla_1]

FYI - the boxes hostname is pikachu

Here are the contents of /etc/mail/sendmail.cw

localhost
S2030089
localhost
Pikachup
localhost
pikachu
pikachu.



Thanks
Jeff

[someone_4]

look at
/etc/resolv.conf

you should have dns servers set up there. Like so

nameserver ip.of.dns.server
nameserver ip.of.another.dns

and /etc/nsswitch.conf

hosts: files [NOTFOUND=continue TRYAGAIN=continue] dns

Richard

[Jeff Paciolla_1]

in my nsswitch.conf file I have the following

hosts : files
aliases : files

I am not using dns, so should I have an /etc/resolv file

Thanks
Jeff

[Jeff Schussele]

Jeff,

If you haven't already, the first thing I would do is double-check that user name at airmessage.net.

You can try to telnet, port 25, to the inbound mail server at airmessage.net.
If you don't know the server name you can perform an nslookup at a root DNS server out on the 'net or from your outgoing or incoming mail servers locally.
#nslookup
>server ip_of_dns_server
>set type=mx
>airmessage.net
>exit

Then #telnet mail_server_ip 25
>HELO
>MAIL From:
>RCPT To: the_user_name@airmessage.net

If it comes back unknown user at this point then that's an invalid username.

HTH,
Jeff

[Clemens van Everdingen]

Hi,

Try putting the names of the exchange relay server in the hosts file and in the /etc/mail/sendmail.cw file.

C.

[Jeff Schussele]

After you get your DNS client set properly, you'll also need to insure your host is in DNS - by hostname & IP as most mailservers do reverse lookups.

Rgds,
Jeff

[someone_4]

You need some way to hostname resolution to be able to send email. Either though hosts or though dns. Other wise airtouch.com doesnt mean anything.

Richard

[Jeff Paciolla_1]

the exchange relay server name and IP are in the hosts file, and when I send an email to myself within ny local domain everything works, when I try to send to an outside (internet) address I get user unknown. I know the outside address is valid.

When I added the relay host name to the sendmail.cw file and stopped and started sendmail nothing worked - I was no longer able to send to myself locally either.

Thanks
Jeff

[Clemens van Everdingen]

Jeff,

Just tried to send you mail to 8773443591@airmessage.net it succeeded as you replied on that mail to my server.

So DNS lookups works fine for me.
So yout problem has really to do with reverse lookups for your pager server.

Regards,
Clemens.

[someone_4]

Try to set your exchange server in the DS in your sendmail.cf for smart relay
the DS can be hostname that is resolved or ip.
like so
DShostname
DS192.xxx.xxx.xx
# "Smart" relay host (may be null)
DS

Richard

[Jeff Paciolla_1]

Clemens - I did get your page. If I am not using DNS are there changes to files that I need to make to get this to work. I have added the host name of my exchange server to the DS portion of the sendmail.cf file. Which everybody says should do the trick, but it does not seem to work for me.

Thanks
Jeff

[Clemens van Everdingen · Accepted solution]

Hi,

This part is the problem:

# nslookup airmessage.net

Using /etc/hosts on: pikachu

looking up FILES
*** No address information is available for "airmessage.net"

So no resolving for airmessage.net !

C.

[someone_4]

Jeff
after you added the DS option did you restart sendmail? Other wise the change wont take.

/sbin/init.d/sendmail stop
/sbin/init.d/sendmail start

Richard

[Clemens van Everdingen]

Hi,

Did you have a /etc/resolv.conf file ?
If we are not using dns you could move it away, and try again.

Also are there any messages in the maillog file ?

C.

[Jeff Paciolla_1]

But shouldn't my relay server take care of the name resolution problem. If i do an nslookup on my relay server i get the following

#nslookup dallasmail
Using /etc/hosts on: pikachu

looking up FILES
Name: dallasmail
Address: xxx.xx.xx.xx

Doesn't this mean that my HP-UX box is talking to my relay server.

Thanks
Jeff

[someone_4]

Jeff
after you added the DS option did you restart sendmail? Other wise the change wont take.

/sbin/init.d/sendmail stop
/sbin/init.d/sendmail start

Richard

[Jeff Paciolla_1]

I did start and stop sendmail after adding the DS line. still no go.

Here is an example from my /var/adm/syslog/mail.log file

Apr 16 14:45:17 pikachu sendmail[21628]: starting daemon (8.8.6 (PHNE_17190)): SMTP+queueing@00:30:0
0
Apr 16 14:45:29 pikachu sendmail[21633]: OAA21633: from=root, size=234, class=0, pri=60234, nrcpts=2
, msgid=<200204161845.OAA21633@pikachu.acs-inc.com>, relay=root@localhost
Apr 16 14:45:29 pikachu sendmail[21635]: OAA21633: to=8773443591@airmessage.net, ctladdr=root (0/3),
delay=00:00:00, xdelay=00:00:00, mailer=esmtp, relay=airmessage.net, stat=Host unknown (Name server
: airmessage.net: host not found)

end example

I don't have an /etc/resolv.conf file since no dns usage

Thanks
Jeff

[someone_4]

Can you send emails form your server to yahoo.com or aol.com??

Richard

[Clemens van Everdingen]

Hi,

Probably that won't work either !

because of this:

relay=airmessage.net, stat=Host unknown (Name server
: airmessage.net: host not found)

This also points to the fact that this server can not find airmessage.net to relay your mail.

C.

[Clemens van Everdingen]

Hi,

How is dallasmail (exchange server) doing his lookups ?

If I do a nslookup from my server to airmessage.net I get the following answer !

[root@webserver log]# nslookup airmessage.net
Server: resolve1.xxxnet.nl
Address: 62.251.0.6

Non-authoritative answer:
Name: airmessage.net
Address: xxx.xx.xx.xx (replaced that)
So this means at least that my webserver can do nslookup to your airmessage.net.
So maybe we need the resolve.conf file to point to some outside dns server to do the lookup !

C.

[Jeff Paciolla_1]

I can send emails to username@yahoo.com with no problems.

Thanks
Jeff