It would be convenient to have a virt-builder oneliner such as
$ virt-builder --arch i386 --ssh-inject ~/.ssh/id_rsa.pub fedora-21
to get an image suitable to run and login with
$ qemu-kvm -m 1024 -net user,hostfwd=tcp::2222-:22 \ -drive file=fedora-21.qcow2 & $ ssh -p 2222 localhost grep PRETTY /etc/os-release PRETTY_NAME="Fedora 21 (Twenty One)"
Docker users have a simpler form because there is no need to ssh to enter the container:
$ docker run fedora:21 grep PRETTY /etc/os-release PRETTY_NAME="Fedora 21 (Twenty One)"
It is not currently possible to use virt-builder as described above because
- the set of images available by default is limited (no i386 architecture for instance)
- the –inject-ssh option is only available in the development version
The libguestfs.org toolbox can however be used to implement a script modifying images prepared for the cloud (see ubuntu cloud images for instance):
- wget the image
wget -O my.img http://cloud-images.ubuntu.com/trusty/current/trusty-server-cloudimg-i386-disk1.img
- create a config-drive for cloud-init to feed it the ssh public key.
mkdir -p config-drive cat > config-drive/user-data <<EOF #cloud-config ssh_authorized_keys: - $(cat ~/.ssh/id_rsa.pub) chpasswd: { expire: False } EOF cat > config-drive/meta-data <<EOF instance-id: iid-123459 local-hostname: testhost EOF ( cd config-drive ; LIBGUESTFS_BACKEND=direct virt-make-fs \ --type=msdos --label=cidata . ../config-drive.img ) - launch the image with the config drive attached and it will be auto detected
qemu-kvm -m 1024 -net user,hostfwd=tcp::2222-:22 \ -drive file=my.img -drive config-drive.img