Tag Archive: ubuntu

I’ve been fine-tuning the configuration of my servers. Some notes from my experiences. One of my VPS’es runs a kernel compiled by the server company. This kernel has disabled IPv6 support. (Why are there still server companies that don’t offer IPv6 in the year 2016? I mean *click*) Anyways… running a kernel without IPv6 makes many daemons throw warnings. I am in particular looking at my mail configuration:

postfix[565]: warning: inet_protocols: disabling IPv6 name/address support: Address family not supported by protocol

To make all these warning gone (they pollute the logs) edit the /etc/postfix/main.cf

inet_protocols = all


inet_protocols = ipv4

When I want to use greylisting on my server, using postgrey. Well… postgrey… will fail when it’s unable to bind to an IPv6 socket. And looking for a configuration file to configure the listning socket??? Where the hell is it. It seems, on a Ubuntu server, we’ll have to look in /etc/default/postgrey. This file specifies the startup parameters when postgrey is started using postgrey service start.

The default value is:


This will try to bind a socket to both IPv4 and IPv6 localhost. In order to make it only bind to IPv4 localhost, change it into


A friend of mine asked if I had a spare PC. Now, I had this PC, an old AMD Athlon, sitting in my storage. The PC had a Debian installation, installed for an event a few years ago, so, it didn’t contain any personal information. Anyways, I decided to re-install the machine. I decided to install Xubuntu. A “n00b-friendly” distro but with a sensible Desktop Environment.

While under Debian the machine worked fine, under Ubuntu, the first issue were graphical glitches and artefacts. The second problem is tha Flash refused to work. Firefox reported the plugin was installed, but it didn’t work. Chromium even refused to start up when the pepper version of the flash plugin was installed. *sigh*

So, I am installing Debian again. It’s a newer then the version that was previously installed, of course, but since Debian worked before, I guess it should work again.
Well…. nope… Under Debian I am having simular issues. Well… Ubuntu and Debian are related. Perhaps I should try something else. I mean… personally I would install ArchLinux, but since I will not be the user for that installation, it should be something n00b-friendly. However…. I might try my Arch installation from another machine, just as a reference. Just to rule our a hardware issue….