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Entry in /etc/hosts should be: 
152.1.115.4 &nbsp; mailhost.papa.za mailhost 
(ip.address &nbsp; fqdn alias) 
And of course mailhost.papa.za has to be resolvable.
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It could be a problem with your DNS settings. 
1) check your /etc/resolv.conf file, to make sure it has the correct DNS server IP: 
eg: 
nameserver ip-of-DNS-server 
2) check /etc/nsswitch.conf file you make sure hostname look up use DNS: 
eg &nbsp;the hosts line looks like 
 
hosts: files dns 
 
If you modify any of the above files, restart sendmail. 

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Hi 
I ahave a problem with one of my servers the server was working fine all allong running sendmail with relay configured on it. When the server sever came up it could npot send or relay emails any more this the error i am getting this error when trying to send an email .... 
 
&nbsp;#echo test | mailx -v myname@so.insite.com 
 
&nbsp;Deferred: Name server: mailhost: host name lookup failure. 
 
I can do nslookup for &quot;mailhost&quot; and i am getting the correct resolution i can also ping &quot;mailhost&quot;. 
 
My /etc/hosts file look like this see &nbsp;below ... 
127.0.0.1 &nbsp; &nbsp; &nbsp; localhost 
152.1.115.4 &nbsp; mailhost mailhost.papa.za mailhost 
 
On My sendmail.cf file the Smarthost is setup this way 
DSmailhost 
 
Also my Daemon options are setup 
O DaemonPortOptions=Name=MTA-v4, Family=inet 
O DaemonPortOptions=Name=MTA-v6, Family=inet6 
O DaemonPortOptions=Port=587, Name=MSA, M=E 
 
 
What is possibley wrong with my setup preventing me to relay messages like i used too ooooH my sendmail configuration version is DZ8.12.10 
 
Please advice 

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Hi
I ahave a problem with one of my servers the server was working fine all allong running sendmail with relay configured on it. When the server sever came up it could npot send or relay emails any more this the error i am getting this error when trying to send an email ....

 #echo test | mailx -v myname@so.insite.com

 Deferred: Name server: mailhost: host name lookup failure.

I can do nslookup for "mailhost" and i am getting the correct resolution i can also ping "mailhost".

My /etc/hosts file look like this see  below ...
127.0.0.1       localhost
152.1.115.4   mailhost mailhost.papa.za mailhost

On My sendmail.cf file the Smarthost is setup this way
DSmailhost

Also my Daemon options are setup
O DaemonPortOptions=Name=MTA-v4, Family=inet
O DaemonPortOptions=Name=MTA-v6, Family=inet6
O DaemonPortOptions=Port=587, Name=MSA, M=E


What is possibley wrong with my setup preventing me to relay messages like i used too ooooH my sendmail configuration version is DZ8.12.10

Please advice


sendmail  Deferred: Name server: mailhost: host name lookup failure

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