Build KaarPux in your own KVM

You can build KaarPux in your own KVM by following the steps below.

The first few steps may seem a bit complicated. And they are, because every system is different. But do not panic! You can always reach out for help on our forum.

Set up a network bridge

In order to enable the KVM instance to have network connectivity, a network bridge must be created.

Find the network interface (if) of your host:

ip addr

Then run:

master/bin/kx_create_bridge <if>

If this does not work for you, some generic information can be obtained from linux-kvm and, and some distribution specific instructions can be obtained from

Configure DHCP

When kvm is started by the scripts explained below, it will be assigned a MAC address of the form 52:54:00:99:00:<nn>, where <nn> is a two-digit value between 10 and 99 you can choose freely. When configuring KaarPux (see below), you should specify <nn> as the value of Tag for this VM.

Your DHCP server should be configured to give this MAC an IP address of x.y.z.<nn>.

As an example: if you are using the 192.168.0/24 IP network, and want to run with <nn> set to 17, make sure that your DHCP server returns IP for MAC 52:54:00:99:00:17.

Select a location for disk images

The disk images used when building KaarPux are by default located under /kvm, which can be a symbolic link to another location.

If you choose another location, you can also set the configuration option Path for image files.

You will need 50-100GB for the build.

Configure KaarPux for KVM

Generic information about configuration can be found in Configure KaarPux.

Run the configuration program:

master/bin/kx_configure ${configuration_file_name} menuconfig

Under Build type select KVM.

Then select Virtual host definitions.

Under Tag for this VM select the <nn> used above for DHCP. In other configuration entries, this number may be referenced by %.

If you did not create a symbolic link for /kvm, specify the intended location for disk images under Path for image files.

Look through the setings under Virtual host definitions; more information about those settings are given in the sections below.

Then select Host definitions and look through the settings; in general the defaults should be sufficient.

For further information see Configure KaarPux.

Create file system images

Create file ssystem images for swap and downloads, as well as for the final KaarPux image:

master/bin/kx_virtual ${configuration_file_name} create_swap_img
master/bin/kx_virtual ${configuration_file_name} create_downloads_img
master/bin/kx_virtual ${configuration_file_name} create_target_img

The names and sizes of the images are defined in the configuration settings under Virtual host definitions.

SSH keys

To avoid using passwords, we connect with SSH using keys.

So, generate a SSH keypair:

master/bin/kx_virtual ${configuration_file_name} generate_ssh_key

The filenames used to store the SSH keypair are defined in configuration settings under Virtual host definitions. The default is ~/.ssh/id_kaarpux

You may also re-use an existing key or generate a new key with:

ssh-keygen <options>

Just make sure to specify the filename for the public key in Virtual host definitions.

Create a host disk image

The first (bootstrap) part of KaarPux is build using an existing GNU/Linux distribution as host.

To create a suitable host disk image:

master/bin/kx_virtual ${configuration_file_name} create_host_img

By default, this will download a Fedora cloud image, create an iso-file called host_<nn>.iso containing meta-data, and from this generate a host disk image called host_<nn>.qcow2

The defaults can be changed in the configuration under Virtual host definitions.

If, for some reason, you want to launch this host disk image under KVM, you can:

master/bin/kx_virtual ${configuration_file_name} launch_host

Download tarballs

Start the host created above and let it download all the source tarballs needed for building KaarPux:

master/bin/kx_virtual ${configuration_file_name} launch_download

This will start a download of source tarballs using the host created above.

Bootstrap KaarPux

Now you are ready bootstrap KaarPux:

master/bin/kx_virtual ${configuration_file_name} launch_build_bootstrap

This will use the host created above to create a minimal bootable version of KaarPux.

By default the bootable disk image will be called kx_<nn>.img, although this default can be changed in the configuration under Virtual host definitions.

If, for some reason, you want to launch this minimal version of KaarPux under KVM, you can:

master/bin/kx_virtual ${configuration_file_name} launch_kaarpux

Build the rest of KaarPux

The rest of KaarPux can now be build inside the bootstrapped KaarPux created above:

master/bin/kx_virtual ${configuration_file_name} launch_build_final

That’s it - you have now build KaarPux!!!

Next steps

Your can now launch the KaarPux disk image:

master/bin/kx_virtual ${configuration_file_name} launch_kaarpux

And connect to it using e.g.:

p=$(( 5900 + ${nn} ))
spicec --host=localhost --port=$p

See also Copying KaarPux to another machine and Post installation.