init-template: Explain how to bootstrap a debian template image

We will build debian vms (oldstable/stable) from a template with some basis
already set-up to avoid repeating those actions for new provisioned vm.

This action is needed to be once in a while (every debian migration to new
stable for example). Still, this is worth documenting/scripting to ease
reproducibility.

Related T1785

proxmox/terraform/init-template.md

+In the following documentation, we will explain the necessary steps
+needed to initialize a template vm.
+
+Expectations:
+
+-   hypervisor: orsay (could be beaubourg, hypervisor3)
+-   \`/usr/bin/qm\` available from the hypervisor
+
+Prepare vm template
+===================
+
+Connect to hypervisor orsay (\`ssh orsay\`)
+
+And then as root, retrieve openstack images:
+
+```
+mkdir debian-10
+wget -O debian-10/debian-10-openstack-amd64.qcow2 \
+  https://cdimage.debian.org/cdimage/openstack/current/debian-10.0.1-20190708-openstack-amd64.qcow2
+wget -O debian-10/debian-10-openstack-amd64.qcow2.index \
+   https://cdimage.debian.org/cdimage/openstack/current/debian-10.0.1-20190708-openstack-amd64.qcow2.index
+mkdir debian-9
+wget -O debian-9/debian-9-openstack-amd64.qcow2 \
+  https://cloud.debian.org/images/cloud/OpenStack/current-9/debian-9-openstack-amd64.qcow2
+wget -O debian-9/debian-9-openstack-amd64.qcow2.index \
+  https://cloud.debian.org/images/cloud/OpenStack/current-9/debian-9-openstack-amd64.qcow2.index
+```
+
+Note:
+
+-   Not presented here but you should check the hashes of what you
+    retrieved from the internet
+
+Create vm
+---------
+
+```
+chmod +x init-template.sh
+./init-template.sh 9
+```
+
+This created a basic vm with basic login/pass as root/test so we can
+connect to it.
+
+Note: Implementation wise, this uses an openstack debian image,
+cloud-init ready [1]
+
+[1] https://cdimage.debian.org/cdimage/openstack/
+
+Check image is working
+----------------------
+
+The rationale is to:
+
+-   boot the vm
+-   check some basic information (kernel, distribution, connection,
+    release, etc...).
+-   adapt slightly the vms (dns resolver, ip, upgrade, etc...)
+
+### Start vm
+
+```
+qm start 9000
+```
+
+### Checks
+
+Login through the console web-ui:
+
+-   accessible from <https://orsay.internal.softwareheritage.org:8006/>
+-   View \`datacenter\`
+-   unfold the hypervisor \`orsay\` menu
+-   select the vm \`9000\`
+-   click the \`console\` menu.
+-   log in as root/test password
+
+Checks:
+
+-   kernel linux version
+-   debian release
+
+### Adaptations
+
+Update grub's timeout to 0 for a faster boot (as root):
+```
+sed -i s'/GRUB_TIMEOUT = 5/GRUB_TIMEOUT = 0/' etc/default/grub
+update-grub
+```
+
+Then, add some expected defaults:
+```
+apt update
+apt upgrade -y
+apt install -y puppet
+systemctl stop puppet; systemctl disable puppet.service
+mkdir -p /etc/facter/facts.d
+echo location=sesi_rocquencourt_staging > /etc/facter/facts.d/location.txt
+
+# for stretch (debian-9)
+# we need a superior version of facter package
+# because we use syntax from that superior version
+cat > /etc/apt/sources.list.d/backports.list <<EOF
+deb https://deb.debian.org/debian stretch-backports main
+EOF
+apt install -t stretch-backports facter
+# for stretch, we also need a superior version of cloud-init
+# the current stable version fails silently to set some cloud-init configuration
+cat > /etc/apt/sources.list.d/buster.list <<EOF
+deb https://deb.debian.org/debian buster main
+EOF
+apt update
+apt install -y cloud-init
+rm /etc/apt/sources.list.d/{buster,backports}.list
+# install cloud-init from buster version (7.9 is too old
+# and prevents some cloud-init functionalities from working)
+userdel debian # remove id 1000 which conflicts with our puppet setup
+```
+-   etc...
+
+### Remove cloud-init setup from vm
+
+```
+# stop vm
+qm stop 9000
+# remove cloud-init setup
+qm set 9000 --delete ciuser,cipassword,ipconfig0,nameserver,sshkeys
+```
+
+Template the image
+------------------
+
+When the vm is ready, we can use it as a base template for future
+clones:
+
+```
+qm template 9000
+```
+
+Clone image
+===========
+
+This is a tryout referenced here to demonstrate the shortcoming. That\'s
+not necesary to do this as this will be taken care of by proxmox.
+
+Sadly full clone only works:
+
+```
+qm clone 9000 666 --name debian-10-tryout --full true
+```
+
+As in: Fully clone from template \"9000\", the new vm with id \"666\"
+dubbed \"buster-tryout\".
+
+Note (partial clone does not work):
+
+```
+root@orsay:/home/ardumont/proxmox# qm clone 9000 666 --name buster-tryout
+Linked clone feature is not supported for drive 'virtio0'
+```
+
+Note:
+
+-   tested with all drives: ide, sata, scsi, virtio
+-   only thing that worked was without a disk (but then no more os...)
+
+source
+======
+
+<https://orsay.internal.softwareheritage.org:8006/pve-docs/chapter-qm.html#qm_cloud_init>

proxmox/terraform/init-template.sh

+#!/usr/bin/env bash
+
+set -x
+set -e
+
+VERSION=${1-"9"}
+NAME="template-debian-${VERSION}"
+IMG="debian-$VERSION/debian-$VERSION-openstack-amd64.qcow2"
+
+VM_ID="${VERSION}000"
+VM_DISK="vm-$VM_ID-disk-0"
+
+# create vm
+qm create $VM_ID --memory 4096 --net0 virtio,bridge=vmbr0 --name "$NAME"
+# import disk to orsay-ssd-2018 (lots of space there)
+qm importdisk $VM_ID $IMG orsay-ssd-2018 --format qcow2
+# finally attach the new disk to the VM as virtio drive
+qm set $VM_ID --scsihw virtio-scsi-pci --virtio0 "orsay-ssd-2018:$VM_DISK"
+# resize the disk to add 30G (image size is 2G) ~> this increases the clone time so no
+# qm resize 9000 virtio0 +30G
+# configure a cdrom drive which is used to pass the cloud-init data
+# to the vm
+qm set $VM_ID --ide2 orsay-ssd-2018:cloudinit
+# boot from disk only
+qm set $VM_ID --boot c --bootdisk virtio0
+# add serial console (for cloud-init, this is needed or else that won't work)
+qm set $VM_ID --serial0 socket
+# sets the number of sockets/cores
+qm set $VM_ID --sockets 2 --cores 1
+
+# cloud init temporary setup
+qm set $VM_ID --ciuser root
+qm set $VM_ID --ipconfig0 "ip=192.168.100.125/24,gw=192.168.100.1"
+qm set $VM_ID --nameserver "192.168.100.29"
+
+SSH_KEY_PUB=$HOME/.ssh/proxmox-ssh-key.pub
+[ -f $SSH_KEY_PUB ] &&  qm set $VM_ID --sshkeys $SSH_KEY_PUB

[Phabricator Migration user]

Some references in the commit message have been migrated:

• T1785 is now infra/sysadm-environment#1785