Everything is a Freaking DNS problem - kvm

Converting KVM to VirtualBox

Kris Buytaert — Tue, 22 Feb 2011 22:01:57 +0000

I have had most of my test environment, aka puppetmasters, test mysql setups etc running in KVM for the past couple of years .. (yes I`m still using a lot of Xen in production environments, but we've also been using KVM for a while already .. it's a good mix) , Virtual box has always been the lesser loved Virtualization platform , however while playing more and more with Vagrant Up I realized I needed to convirt some boxen (e.g my PuppetMaster) to Virtualbox, and google was really no good help(most people seem to go the other way , or want to use some proprietary tools )

So I remembered VBoxManage and apparently I hade blogged about it myselve already ..
I just hate it when I search for stuff and google points right back to me

So I converted my puppetmaster's disks

VBoxManage convertdd Emtpy-clone.img  PuppetMasterroot.vdi
VBoxManage convertdd puppet-var.img  PuppetMastervar.vdi

Now when booting the VM in Virtualbox , obviously the kernel panicked .. as my KVM disks are recognised as as /dev/hda and and Virtualbox defaults to /dev/sda and LVM doesn't really like disks to be on another names
No commandline fu here to help me, but using the VirtualBox gui to move the disks to the IDE controller rather than the SATA controller.

Now all I need to do is wait for some smart guy who comments that you probably could use VBoxManage storagectl to achieve the same goal :)

And wait till Vagrant Up start supporting KVM , so I can move back :)

Building Virtual Appliances

Kris Buytaert — Thu, 27 May 2010 08:03:29 +0000

Johan from Sizing Servers asked me if I could talk about my experiences on building (virtual) appliances at their Advanced Virtualization and Hybrid Cloud seminar . Off course I said yes ..

Slides are below ... Enjoy ..

Building appliances

View more presentations from Kris Buytaert.

Disabling DHCP on a LibVirt setup

Kris Buytaert — Fri, 04 Dec 2009 18:43:27 +0000

So you have this libvirt setup and you want to have a dhcp server on the virtual machines you are playing with , or you want to have all static IP's.

Libvirt uses dnsmasq to provide dhcp services etc and when you generate a config from the gui it will look like

<network>
  <name>piponet</name>
  <uuid>e87d3bf1-a2e7-96ca-e131-7ae51ac033f9</uuid>
  <bridge name='virbr2' stp='on' delay='0' />
  <ip address='192.168.100.1' netmask='255.255.255.0'>
    <dhcp>
      <range start='192.168.100.128' end='192.168.100.254' />
    </dhcp>
  </ip>
</network>

If you fully remove the dhcp section, then restart libvirt you'll notice dnsmasq running with no dhcpd on that subnet so you'll have full control again :)

<network>
  <name>piponet</name>
  <uuid>e87d3bf1-a2e7-96ca-e131-7ae51ac033f9</uuid>
  <bridge name='virbr2' stp='on' delay='0' />
  <ip address='192.168.100.1' netmask='255.255.255.0'>
     </ip>
</network>

KVM vs Virtualbox

Kris Buytaert — Thu, 30 Jul 2009 19:33:17 +0000

So you need that old FC9 instance on your fresh F11 install.

Obviously I started a KVM instance on my desktop and installed FC9 in a Virtual Machine,
It took long to install, too long, so I looked if KVM was working correctly
Kvm was loaded but not in use ..
And then you remember why you had VirtualBox on that machine before it's upgrade . indeed, this machine was to old it was not a VT Capable machine . VirtualBox performs much better there ..

But you already have a working installed Qemu image.
What do you do ? Google tells you about vidtool but all you find are broken links ..

So you look further and you find that you can use VBoxManage for the same functionality

VBoxManage convertdd FC9.bin FC0.vdi

KVM or Xen

Kris Buytaert — Mon, 06 Jul 2009 20:47:17 +0000

Over at Virtualization.com I asked the crowd what they planned to do when RedHat plans on finally migrating from Xen to KVM .. you can have your say too . :

Slides updated

Kris Buytaert — Tue, 31 Mar 2009 17:04:55 +0000

I've updated the slidedeck of my Open Source Virtualization talk, with the 2009 edition as I gave it last week at the UKUUG Spring conference.

Talk is up, both on my page as on SlideShare

open source virtualization

View more presentations from Kris Buytaert.

Tom also updated our set of Open Source Monitoring Tool Shootout slides .
They are also on SlideShare

Open Source Monitoring Tools Shootout

View more presentations from tomdc.

UKUUG Spring 2009 Conference , here we come

Kris Buytaert — Tue, 24 Mar 2009 20:11:21 +0000

I`ll be heading to bed early today as tomorrow will be a busy day. I have to get up early to catch my flight to London where
Tom and I will be representing Inuits at the UKUUG 2009 Spring Conference.

Tom will be giving an updated version of our Open Source Monitoring Shootout talk again, I`ll probably be skipping a couple of his slides as right after that Jane Curry will be covering Zenoss in depth and on thursday there will be an OpenNMS talk too.

On Thursday I will be giving another session of my Open Source Virtualization overview talk .. and I also plan on skipping slides and referring to the next speaker, as Matt will be giving an openQRM talk right after me :)

See you there !

Open Source Virtualization

Kris Buytaert — Sat, 04 Oct 2008 11:18:26 +0000

I've just placed the presentation I gave both yesterday at the Open Source Days in Copenhagen , and last week in Zurich at the Open Expo , about Open Source Virtualization online.
The presentation is based on a series of articles I wrote earlier this year for Virtualization.com

You can download it here

The presentation covers a fairly complete overview of what's around in Open Source Virtualization tools and and their Management frameworks.

I will be giving the same presentation again at the end of the month at T-Dose in Eindhoven, The Netherlands

Excuses

Kris Buytaert — Tue, 06 May 2008 18:04:15 +0000

Hmm.. need to find one to go here

VMWare Revisited

Kris Buytaert — Thu, 31 Jan 2008 17:58:40 +0000

Last century I was sometimes noticed to be using VMWare to run a weird platform on my Linux Desktop , or to run some test installations. With the introduction of Qemu and later Xen there was no need for me to use the proprietary closed alternative.

So I got the question earlier this week to build a virtual instance of our bootstrapping environment so that field engineers could take that virtual machine on their laptop and do installations from there.

One of the collegues told me that booting a fresh VMWare instance of the network would be no problem so I took up on the challenge.

First of all a registration procedure so the nice folks over at VMWare can spam me with their marketing stuff during the next couple of months. I needed to register as I seemed to need a Serial Number.. whow .. that was ages ago since I last needed such a beast.
A full 101Mb download later I had an RPM ready to be installed.

"Cool an RPM" I tought, that means that I will be able to clean up all the mess they leave behind with a simple rpm -e.
Wrong guess. it seems like VMWare starts copying around files in different places on your filesystem and actually even wants to compile stuff against your running kernel. All fine and well, but the result is a bunch of unidentified files that are cluttering my filesystem.

The next step required me to start the gui to create a virtual machine, suddenly the load of my machine skyrocketed. Load 11 whew.. yep the VMware process was the guilty one.. luckily it went back to normal after a while .. but I`m still not sure what happened there.

Click, click, click and before I knew it VMware was allocating 4Gb on myfilesystem for an empty VM. Noo.. don't allocate it yet.. retry.. ok .. take it when you need it .. that's better. And why do you think I only want 256Mb for this machine ? Hmm.. where's that config file.. aah.. clickerdy click again .

Start VM, F12 to boot of the network, wait, reboot done.

And thus we joined the era of transferring an unmanagable image that everyone will copy around wile slightly modifying things and never placing them in version control . hence ending up one day with something nobody knows how we got there..

What did we learn, that the way I bootstrap a Virtual machine or a physical machine really doesn't matter, and is still just a matter of mapping a MAC address to a HOSTNAME.

When working on the system, to check if the install was done correctly it felt like I was on a remotely bad connected machine, not really slow, but really slow but still (could have been because I logged on via the gui). Certainly not like the paravirtualized Xen machines I`m used to work with, more like the VirtualBox experience.

The big problem with giving someone an image to play with however is that you loose all control over what is being deployed , configured or changed and it just becomes a change management nightmare. At least reinstalling won't take much time.

But I`ll go back to KVM and Xen for my daily work.. I've seen enough GUI's for this month :)