Postfix - MX: host nof found

systemctl status postfix postfix/smtp[26134]: 1146A41C9018: to=, orig_to=, relay=none, delay=0.03, delays=0.01/0.03/0/0, dsn=4.4.3, status=deferred (Host or domain name not found. Name service error for name=mail.example.com type=MX: Host not found, try again) Be sure you have correct settup /etc/resolv.conf and all permissions are okay for postfix user sudo -u postfix -H cat /etc/resolv.conf you have here some DNS server if not you can try autogenerated by network-manager: set this option to your /etc/sysconfig/network-scripts/ifcfg script. PEERDNS=yes this command will print on first line a number of mails in que time mailq | grep -c '^[0-9A-Z]' this will force resend all messages postqueue -f