This week the first official CentOS Dojo in Cologne was taking place. CentOS Dojos are one-day events where administrators and developers can exchange knowledge. Talks about recent topics are always part of these events.

inovex GmbH kindly features the event by providing their rooms and hearty catering. Beside coffee …

Files can be easily transfered from an Android device to Windows computer using MTP (Media Transfer Protocol). Unfortunately this protocol is not supported in Finder which means that you need to connect your smartphone as hard drive - if this function is supported.

My Android 4.4.x ROM isn't supporting this function …

OpenVPN connections can be established under Mac OS X using the free software Tunnelblick - I kept in mind.

Using the most recent OS X version Mavericks this is a problem. The stable version of Tunnelblick is not ready yet for Mavericks which means that it is necessary to use beta version. Unfortunately those were not …

Recently I was confused when I spotted several spam comments on my blog. After logging into the Wordpress administration page I saw the reason for this issue:

1Akismet has detected a problem. A server or network problem is preventing Akismet from working correctly.

Oops - where did that come from?

It seems like my …

While importing the recent EPEL7 YUM repositories I stumbled upon the following error:

1# /usr/bin/spacewalk-repo-sync --channel epel-el7-x86_64 
2> --url http://dl.fedoraproject.org/pub/epel/beta/7/x86_64/ 
3> --type yum -c epel-el7-x86_64
4Repo URL: http://dl.fedoraproject.org/pub/epel/beta/7/x86_64/
5ERROR: xz …

It is possible that RHEL7 channels aren't available to Red Hat Satellite even though you're having a valid Red Hat Enterprise Linux subscription.

The appropriate software channel (rhel-x86_64-server-7) is not part of the list of available channels - it also cannot be downloaded manually:

1# satellite-sync …

While bringing my self-made ESXi hosts into service I saw that only one of two network cards was detected. The reasons for this issue was that VMware ESXi offers no driver for the second network card Intel 82579LM.

What a pity. Fortunately I stumbled upon a blog which offers an adequate software packages which was …

At about two years ago I replaced a lot of my hardware with more power-saving alternatives. My self-made NAS and hypervisor wer replaces by two HP ProLiant MicroServer G7 servers (N36L and N40L) - for a long time I was very happy with them.

In the last months the amount of VMs increased and now the CPU and memory …

Beside Linux systems also Oracle Solaris hosts can be managed using Spacewalk and Red Hat Satellite - a cool feature that is often forgotten. (Update: since Spacewalk 2.2 from 07/16/2014 this function is "deprecated" which means that it might be removed in one of the following releases)

Bigger companies which …