The original message was received at Wed, 1 Jun 2016 04:37:53 +0300 from tin.it [131.4.232.235] ----- The following addresses had permanent fatal errors ----- dev at openvswitch.org ----- Transcript of session follows ----- ... while talking to openvswitch.org.: 550 5.1.2 <dev at openvswitch.org>... Host unknown (Name server: host not found)