Sendmail relaying problems

[Emma Cooper_1]

Can anyone help? Why won't sendmail forward e-mails to another host in my LAN? I have set the Smart Relay option up in the .cf file and using sendmail -bv joe@adomain.com shows that the message is deliverable. Any non local messages simply remain in the queue and do not get forwarded.

Any pointers would be appreciated.

Emma

[Berlene Herren]

Emma, what version are you running? (sendmail -bs will return this). By default 8.9.3 does not allow relay, you have to "turn it on." Take a look at the documentation under /usr/share/doc.

Berlene

[Emma Cooper_1]

Belene

Sendmail version is 8.8.6.

Does not setting the relay host in the cf file switch on relaying? Would the fact that this UNIX machine has no access to DNS servers be a problem. The relay I wish to use obviously does. The output from a sendmail -v command is:

#sendmail -v carolyn@atlasnet.net.ma carolyn@atlasnet.net.ma... atlasnet.net.ma: Name server timeout

carolyn@atlasnet.net.ma... Transient parse error -- message queued for future delivery

[Berlene Herren · Accepted solution]

Exactly. Sendmail goes to DNS first for MX record.

If you can successfully nslookup that mail relay server, then let's try this:

cp /usr/newconfig/etc/nsswitch.conf /etc

Then set the hosts line like so

hosts: files

Try sendmail then.

Berlene

[Albert E. Whale, CISSP]

Emma,

You want to configure Sendmail to use the Smart Relay Host.

First off, you'll need something like the following:


Cwlocalhost
# file containing names of hosts for which we receive email
Fw/etc/sendmail.cw

# my official domain name
# ... define this only if sendmail cannot automatically determine your domain
#Dj$w.Foo.COM


CP.

# "Smart" relay host (may be null)
DS


Change the DS command to DS and the FQDN (Fully Qualified Domain Name). This name needs to be resolvable with the nslookup command (in whatever format you want to use).

Make sure that the FQDN is in the /etc/hosts file, if this node does not have DNS. The onther thing that you want to check is that your Domain of the non-DNS aware not be the same as the Smart Relay Host. This is expected because Sendmail will attempt to deliver to everything within it's Domain, without a Relay Server.

Hope that helps.

[Emma Cooper_1]

Berlene

That's it. Changing the nsswitch.conf has resolved the problem.

Many thanks

Emma

[Berlene Herren]

Excellent Emma, glad I was able to help!
Berlene