sendmail : 550 host unknown

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# 1  
Old 11-03-2001
sendmail : 550 host unknown


I try to configure snedmail as smtp for my solaris box. if the useres are local there's no problem everything's working fine, but is it outside, sendmail says it could find the host. why?! all other tools find diffrent host?
Could anyone tell me how I set up an easy mx ? So I test it with nslookup set querytype=mx and get email host for diffrent domains. How could I tell this infos sendmail ?

# 2  
Old 11-03-2001
Domain Name System (DNS)

Sounds like a DNS name resolution issue. What namesever are you using? Please post the output of:

cat /etc/resolv.conf

# 3  
Old 11-04-2001
RE : Domain Name System (DNS)

here it is

# 4  
Old 11-04-2001
Hmmm. DNS server seems to be working fine......

Might be the old NIS switch problem in Solaris. See if this thread/post helps:

Or the entire DNS/NIS thread from the first page:

Let us know if this helps.... if not, we can try another approach to troubleshoot the problem....
# 5  
Old 11-05-2001
Sorry I don't get the right informations in these theards.

I think sendmail just coulnd't connect to the dns for mx/nslookup. I tried it manually and it works and get mx information of any host I want to know.

Is there any additional special dns config for sendmail name resolving ?

I think a is a bit strange then all other parts could resolv it without any problems.

I just want a simple smtp. I dont need any more.

I read about more and more tools. I don't need any named.conf don't you? Or did I misunderstand something!

It should really be an easy going smtp - no more.

Thank you for your help!!!
# 6  
Old 11-05-2001
No, you don't need named.conf, that is for running a name server; you have a working nameserver already. sendmail uses a name resolution 9resolver) API to resolve hostnames. So does telnet, ftp, etc. Can you telnet to another host from the same server?

telnet ??
# 7  
Old 11-06-2001
Yes I can connect anywhere from this server! There's also running apache, fpt, telnet etc.

And I administrate the server on console from another station, and often i open ftp on this server to download tar gzs like apache, php etc...

Just ask for namend.conf because i wans't sure about it. but when I do it manually by nslookup on the solaris box. I get all mx result diffrent hosts.
tryout for

> set quertype=mx

Nicht-autorisierte Antwort: MX preference = 100, mail exchanger = MX preference = 10, mail exchanger = internet address = internet address =

so the dns resolver works...

also could I send Mails to my server via smtp... but it's like my nslookup example. I get a postmaster message that it could find the host, but by nslookup, on the same server... it find the host!!! There's a brocken pipe between sendmail and dns resolving... im a bit confused about that!

So I don't know what I do wrong. And I'm not new to unix. So where are additional config for sendmail to dns resolv. I don't find more than resolving entrie.

thank you!
.... i dont really what's wrong.
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