xen

2009’s Virtualization Techniques Compared

June 4, 2009 in Computer, Hardware, Network, Security, Software, Unix

Hi folks, before we get started a small explanation of my setup and why I want to replace it.
My small home server runs Xen 3.3 with Ubuntu Intrepid, a Debian Xen kernel and the guests on LVM devices. Guest OSs vary from Debian over Solaris to Windows. I built the server last year, but sadly I’m already running out of HDD space and want to upgrade soon. I also want to re-install the Dom0 because Intrepid doesn’t run very well: USB doesn’t work with all devices, there are some bugs in the start-up scripts and I have trouble with the ttys.
A lot has changed since I last fiddled with virtualization so I used this weeks bad weather to compare the current status of all those virtualization systems.
Because there are so many different needs, there are many specialized solutions for desktop and server virtualization. Open-Source, free or commercial ones.

I use VirtualBox on my workstation because it’s free, fast, easy to use and runs very very well. I’ve used the VMware products earlier on Linux and Windows until they became too feature-rich, slow and sometimes even buggy for me. But this post is not about desktop virtualization, it’s about open-source (or free) server virtualization.

VMware Server, VMware ESXi, Microsoft Hyper-V, VirtualBox, Xen and KVM are the ones I’ve tried. There is also Virtuozzo, OpenVZ, UML and so on, but these are more like chroots on steroids. Continue reading to see what I liked and what I didn’t like about them.

help.ubuntu.com links to my blog

June 1, 2009 in Computer, I'm Bitching, Unix

I was just comparing the current status of KVM, Xen and some other virtualization techniques when I came across the Ubuntu Help for Xen. The page states that Ubuntu still doesn’t provide a Xen Dom0 Kernel in their latest release, but that doesn’t surprise me becaus Xen still didn’t make it into the official Kernel… maybe because everyone loves KVM that much. But they link you to a blog post which shows how to run Xen on Ubuntu anyhow.

Noticed it? Yes that’s my article. I was really surprised to see a link to my actually pretty provocative article on an Ubuntu site. They could have also linked to bderzhavets article.

So… that’s it for now. I’ll continue comparing virtualization techniques with the help of debian-user-german and will hopefully begin with the reinstallation of my xen host.

How-To: Run Xen in Ubuntu Intrepid without compiling a Kernel by yourself

December 12, 2008 in Computer, How-To, Unix

Update: Also read my Article about current Virtualization Techniques

I got some strange errors when I tried to run OpenSolaris on Hardy as a HVM domain. These errors were fixed in 3.3, but Ubuntu Hardy doesn’t have Xen 3.3 and there were no backports at that time (don’t know if there are ones now) so I upgraded to Ubuntu Intrepid an then noticed that Canonical has dropped Xen Dom0 support. Great! Why the heck did they drop Xen? Because KVM is cooler? Or because they didn’t want to blame themselves by releasing another totally buggy self-patched Dom0 kernel? I mean they didn’t even manage to provide a working one later on so the community had to…and thats a LTS release? WTF?

O.K. well… You want Xen 3.3 with it’s improvements? You don’t want to switch the distro? You don’t want to compile on your own? Here’s how I did it with Ubuntu Intrepid:
I used the Xen 3.3 Hypervisor and Utils coming with Intrepid and then stole a Dom0 kernel from Debian. Debian has linux-image-2.6.26-1-xen-amd64 and linux-modules-2.6.26-1-xen-amd64. I installed both packages and by now everything works great.

O.K. I called this post How-To so here comes how to install the Debian packages on Ubuntu. I will only show you how to install them by hand, you could also add the Debian repos to your sources.list and use pinning.

wget http://ftp.de.debian.org/debian/pool/main/l/linux-2.6/linux-modules-2.6.26-1-xen-amd64_2.6.26-10_amd64.deb
wget http://ftp.de.debian.org/debian/pool/main/l/linux-2.6/linux-image-2.6.26-1-xen-amd64_2.6.26-10_amd64.deb
sudo dpkg -i linux-modules-2.6.26-1-xen-amd64_2.6.26-10_amd64.deb
sudo dpkg -i linux-image-2.6.26-1-xen-amd64_2.6.26-10_amd64.deb
wget http://ftp.de.debian.org/debian/pool/main/l/linux-2.6/linux-modules-2.6.26-1-xen-amd64_2.6.26-12_amd64.deb
wget http://ftp.de.debian.org/debian/pool/main/l/linux-2.6/linux-image-2.6.26-1-xen-amd64_2.6.26-12_amd64.deb
sudo dpkg -i linux-modules-2.6.26-1-xen-amd64_2.6.26-12_amd64.deb
sudo dpkg -i linux-image-2.6.26-1-xen-amd64_2.6.26-12_amd64.deb

Or find the latest using these links: modules kernel
That’s it. There are no other depends. Just reboot. The new kernel should now be the default one. But keep in mind that this is just a workaround.

If I should ever reinstall this Xen-Server: I WILL NOT USE UBUNTU ANYMORE! All these annoying stupid errors… Maybe Debian or CentOS. I mean… I like Ubuntu, it’s a great beginner distro and even lets the nerds control everything they want, but what Canonical delivered the last few months just sucks. All these annoying bugs they added by patching arround: Non-working sound, A buggy KDE4. O.K. you could say that’s all desktop related stuff, but on my server for example I had some very strange XFS errors with the Ubuntu-Server kernel that just disappeared with the (also newer, maybe that’s the point) Debian kernel.