published by whitemice on Thu, 12/10/2020 - 14:58
I have a postfix SMTP relay buried deep in a network behind proxy servers, all the infrastructure [sadly] is IPv4 only. This works, yet one ends up with many log messages like:
connect to smtp.office365.com[2603:1036:304:2857::2]:587: Network is unreachable
The server attempts if IPv6 result from the DNS lookup first. So let's make postfix use IPv4 only.
postconf -e inet_protocols=ipv4
That's it! No more "unreachable" log messages.
published by whitemice on Wed, 07/08/2009 - 00:00
A great post over on Ivan Zlatev's BLOG on how to get a working configuration of multiple network interfaces on a Microsoft Windows workstation. There probably isn't anyone who has been forced to use that runt of an OS and not been frustrated by how it handles network connections.
