Linux Mail Delivery Failed With DNS Service Unavailable Error and Solution

last updated June 5, 2008 in Bind dns, CentOS, Debian / Ubuntu, EMail Servers, Linux, Networking, RedHat and Friends, Troubleshooting, Ubuntu Linux

Q. I get following error message for my postfix email server:

Mail Delivery Failed With DNS Service Unavailable Error and Solution

How do I fix this problem?

A. You need to setup full qualified domain name (FQDN) using dns server to avoid this error message. The remote mail server receiving the mail from the local server is unable to resolve the local mail server’s hostname. For example, if you set local mail server name to lansmpt.example.com, make sure it can be queried using DNS and have a valid working fully qualified domain name.

Posted by: Vivek Gite

The author is the creator of nixCraft and a seasoned sysadmin, DevOps engineer, and a trainer for the Linux operating system/Unix shell scripting. Get the latest tutorials on SysAdmin, Linux/Unix and open source topics via RSS/XML feed or weekly email newsletter.

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Tagged as: domain name, email server, error message, hostname, Linux, local mail, mail delivery, mail server name, remote mail, server mail