FQDN problem, maybe bad configuration postfix?

I have a problem with sending email on some servers. Maybe solution will be rid off .localdomain from recipient address. But i don’t know how.

I can send emails to varied domain, even gmail has no problem but some return mail with error, for example:

email@azet.sk: host smtp2.azet.sk[] said: 554 5.7.1
email@azet.sk: Recipient address rejected: Invalid HELO/EHLO; Cannot
resolve ‘fantasyshop.localdomain’, no such domain (in reply to RCPT TO

Reporting-MTA: dns; fantasyshop.localdomain
X-Postfix-Queue-ID: 60D373602F63
X-Postfix-Sender: rfc822; fantasyshop@fantasyshop.sk
Arrival-Date: Wed, 27 Mar 2013 15:35:22 +0100 (CET)

Final-Recipient: rfc822; email@azet.sk
Action: failed
Status: 5.7.1
Remote-MTA: dns; smtp2.azet.sk
Diagnostic-Code: smtp; 554 5.7.1 email@azet.sk: Recipient address
rejected: Invalid HELO/EHLO; Cannot resolve fantasyshop.localdomain’, no
such domain

I looked for solutions almost 2 months but i could not find out the right one for my problem.

Thanks for any advice,

PS: Sorry for my English


Yeah, it does seem as if it may be an issue with the hostname.

What output do you receive if you run this command:



Here is output:

user@fantasyshop:~# hostname

user@fantasyshop:~# hostname -f fantasyshop.sk

Thank you for further advice.


Hmm, I’d recommend changing your hostname to an FQDN… something like “host.domain.tld”.

You can change that in Webmin -> Networking -> Network Configuration -> Hostname and DNS Client.

After doing that, restart Postfix using this command:

/etc/init.d/postfix restart

After performing the above steps, does that resolve your issue?


Thank you, Eric,

Looks like my problem is solved. It was my fault with understanding FQDN. I thought it means just domain name without any prefix before it.

One question for future. Do i need add any A name to DNS records for host? I mean, when i put host.domain.tld, do i need put host to A record or to any config file in system?

Sorry for my noobish questions, just want to make it right :slight_smile:

Thank you again.