How to fully automate unattended virt-install? - virtualization

Question

Let me start by saying what I want to do. I'd like to fully automate, in an unattended way, the building of QEMU/KVM VM images using virt-install. I know that some folks use the GUI tool to do this, or they edit a pre-existing image's XML description, but I want to start from scratch.
I've Googled around and examples of doing this are hard to find. What I have found is that virt-install is the command to use, and that it can be used interactively with a TTY console attached (you manually answer configuration questions during the install). For a fully automated solution, you can specify a kickstart file (typically preseed.cfg) to provide answers to questions that you'd normally enter manually. The kickstart file can also specify additional software to install, disk and network configuration, etc.).
I think I've got this mostly working except that the installation hangs shortly after install begins. I think it has something to do with the need (or not) to have a console attached to the install. Here is the virt-install command I am using:
virt-install --connect qemu:///system \
--name vm --ram 128 \
--disk path=./vm.qcow2,size=8,format=qcow2 \
--location 'http://archive.ubuntu.com/ubuntu/dists/trusty/main/installer-amd64/' \
--network user,model=virtio \
--initrd-inject preseed.cfg \
--extra-args="console=tty0 console=ttyS0,115200"
This is the preseed.cfg file (which I cribbed from many examples on the web and in the Ubuntu documentation):
### Localization
# Locale sets language and country.
d-i debian-installer/locale string en_US
# Keyboard selection.
d-i keyboard-configuration/layoutcode string us
d-i keyboard-configuration/modelcode string pc105
d-i keyboard-configuration/variantcode string
### Network configuration
# netcfg will choose an interface that has link if possible. This makes it
# skip displaying a list if there is more than one interface.
d-i netcfg/choose_interface select auto
# Any hostname and domain names assigned from dhcp take precedence over
# values set here. However, setting the values still prevents the questions
# from being shown, even if values come from dhcp.
d-i netcfg/get_hostname string vm
d-i netcfg/get_domain string foobar.net
# Disable that annoying WEP key dialog.
d-i netcfg/wireless_wep string
### Mirror settings
d-i mirror/country string manual
d-i mirror/http/hostname string us.archive.ubuntu.com
d-i mirror/http/directory string /ubuntu
d-i mirror/http/proxy string
### Partitioning
# Encrypt your home directory?
d-i user-setup/encrypt-home boolean false
# Alternatively, you can specify a disk to partition. The device name
# can be given in either devfs or traditional non-devfs format.
d-i partman-auto/disk string /dev/vda
# In addition, you'll need to specify the method to use.
# The presently available methods are: "regular", "lvm" and "crypto"
d-i partman-auto/method string regular
# You can choose from any of the predefined partitioning recipes.
d-i partman-auto/choose_recipe select atomic
# This makes partman automatically partition without confirmation, provided
# that you told it what to do using one of the methods above.
d-i partman-partitioning/confirm_write_new_label boolean true
d-i partman/choose_partition select finish
d-i partman/confirm boolean true
d-i partman/confirm_nooverwrite boolean true
### Clock and time zone setup
# Controls whether or not the hardware clock is set to UTC.
d-i clock-setup/utc boolean true
# You may set this to any valid setting for $TZ; see the contents of
# /usr/share/zoneinfo/ for valid values.
d-i time/zone string UTC
### Account setup
# Skip creation of a root account (normal user account will be able to
# use sudo).
d-i passwd/root-login boolean false
# To create a normal user account.
d-i passwd/user-fullname string VMuser
d-i passwd/username string vmuser
# Normal user's password, either in clear text
# or encrypted using an MD5 hash.
d-i passwd/user-password-crypted password CRACKMECRACKM
# This is fairly safe to set, it makes grub install automatically to the MBR
# if no other operating system is detected on the machine.
d-i grub-installer/only_debian boolean true
### Package selection
d-i tasksel/first multiselect standard
# Individual additional packages to install
d-i pkgsel/include string openssh-server
### Finishing up the first stage install
# Avoid that last message about the install being complete.
d-i finish-install/reboot_in_progress note
# How do you want to manage upgrades on this system?
d-i pkgsel/update-policy select none
After all that, when I execute the virt-install command I see:
WARNING Unable to connect to graphical console: virt-viewer not installed. Please install the 'virt-viewer' package.
WARNING No console to launch for the guest, defaulting to --wait -1
Starting install...
Retrieving file linux...
Retrieving file initrd.gz...
Allocating 'virtinst-linux.rCdX0h'
Transferring virtinst-linux.rCdX0h
Allocating 'virtinst-initrd.gz.BbRBMv'
Transferring virtinst-initrd.gz.BbRBMv
Creating domain...
Domain installation still in progress. Waiting for installation to complete.
and it just hangs. If I ^Z into the background and start virsh I see the vm in a running state.
I think I'm close, but need to fix it so that:
Install shows complete and virt-install returns to shell.
The new VM is shutdown and I'm left with the image file ready to go.
I think #2 can be accomplished in the preseed.cfg file with some kind of cleanup instructions (still researching this), but any help of fixing #1 would be greatly appreciated.

Answer 1

To have virt-install use a Kickstart file to initialize an operating system, you need to pass the ks= argument to the kernel by specifying it via the --extra-args parameter:
--initrd-inject preseed.cfg \
--extra-args="ks=file:/preseed.cfg console=tty0 console=ttyS0,115200"
The above example injects a local Kickstart file onto the guest operating system, to be used for automated installation.
You can also specify ks via HTTP:
--extra-args="ks=http://192.168.1.1/preseed.cfg"
or FTP:
--extra-args="ks=ftp://192.168.1.1/preseed.cfg"
or NFS:
--extra-args="ks=nfs:192.168.1.1:/preseed.cfg"