/Blog/

Change KVM/Ganeti Storage Controller For A Windows Guest

2017-11-09T10:20:28+00:00Autor: Daniel Morlock

The old Windows 2003 Server of a customer, which was mentioned in an earlier post, encountered some problems since the last windows update. Varied blue screens indicated a problem with the virtual storage controller. As this was still an virtual IDE controller, an update to the VirtIO SCSI drivers was the logic step to do. Many sources I found on the internet on this topic suggested to reinstall/repair-install Windows, but this was not a possibility. This post sums up how to change the storage controller of a Windows installation without reinstalling Windows. The reason why someone wants to do this is a change of the hard disk (from IDE to SATA, from physical to virtual, etc.) or a replacement of controller hardware, e.g. your motherboard

OCSP Stapling on Nginx

2017-11-09T10:20:01+00:00Autor: Daniel Morlock

OCSP (Online Certificate Status Protocol) is an internet protocol used for obtaining the status of SSL certificates. It was created as an alternative to CRL (Certificate Revocation Lists) and is described in RFC 6960. In this post I'll try to explain the differences between CRL and OCSP and what OCSP stapling is good for. CRL and OCSP Here is how certificate validation is supposed to work: Browers and other clients are supposed to check somehow if the certificate some HTTPS website presents to them is still valid or was already revoked for some reason. In case of CRLs the client downloads a list, which contains a number of serial numbers of certificates which are no longer valid. The problem here is, that in order to access an HTTPS website, the

Kolab 3.2 for Gentoo is ready to rumble

2017-11-09T10:23:34+00:00Autor: Daniel Morlock

Just in time for the official Kolab 3.3 release, our Gentoo packages for Kolab 3.2 became stable and ready to use. This will clear the way for the upcoming release of Kolab 3.3 for Gentoo. Altough this release won't bring any major changes, it prepares the ground for upcoming developments and new features in Kolab 3.3. Further, with Kolab 3.2 we introduced an upgrade path between Kolab releases for Gentoo and we will try our best to keep updates as consistent and comfortable as possible. A lot of work has been done by the Kolab developers to support the new features of the upcoming Cyrus IMAP 2.5 including support for event notifications, xconversations and full-text indexing. Unfortunately, Cyrus 2.5 is neither announced on the Cyrus

Migrate Windows 2000/XP/2003 from VMWare to Ganeti/KVM

2017-11-09T10:14:53+00:00Autor: Daniel Morlock

The migration of a virtual Windows 2003 Server system from an existing VMWare ESXi 5.0 machine to a new Ganeti cluster based on KVM was way harder than expected. The process discribed on this page should work for other virtualisation platforms as well. Just replace the Ganeti and ESXi specific commands with the corresponding commands of your virtualisation software. Prepare it! Before we start, it is important to know that without the appropriate modifications to the registry, a Windows 2000/XP/2003 Server refuses to boot from a new disk controller. Hence before shutting down the virtual machine, you have to install this registry patch available from the Microsoft Knowledge Base. Just follow the instruction of the knowledge base article to install the registry patch. This concerns

CalDAV/iCAL Support for Kolab

2017-11-09T10:14:31+00:00Autor: Daniel Morlock

The Kolab groupware is a great open source alternative to well known closed source groupware solutions. For example, the Kolab groupware has most of the features of Google Mail including mail, calendar, contacts and supports sharing of those entries between users. Since Kolab 3.1 there is also CalDAV and CardDAV support included via a SabreDAV based protocol layer called iRony. This turns Kolab into a CalDAV/iCAL server that enables synchronization of Kolab stored calendars and contacts with any CalDAV/CardDAV supporting device, e.g. Android or iOS based smartphones and tablets. However, Kolab still has no CalDAV/iCAL client support, meaning that adding external calendar resources such as holiday calendars, birthday calendars, shared Google Calendars or any kind of external CalDAV/iCAL calendars is not possible so far. Therefore

Kolab meets Gentoo Linux

2017-11-09T10:14:22+00:00Autor: Daniel Morlock

Kolab is a free groupware based on Postfix, Cyrus IMAP and Roundcube. The groupware includes email, calendars, addressbooks, task management and a wide variety of clients. Since version 3.1 Kolab also supports the standardized CalDAV and CardDAV protocols so that all data can be synced to a phone, tablet or any CalDAV/iCAL client. More than enough to have a closer look. Kolab is community driven and has enterprise support by Kolab Systems AG. Next to the enterprise version, they also provide community packages for RHEL and CentOS. The source code is available from their Git repositories. An openSUSE Build Service provides additional testing packages for Debian, Fedora, OpenSUSE and Ubuntu. Unfortunately, the Gentoo support for Kolab seemed to starve for some reason. We only found