Initial commit: MAAS-deployable Proxmox VE images with cluster automation

Builds a Proxmox VE image that MAAS can deploy to bare metal, plus first-boot
automation that configures the node and joins it to a Proxmox cluster with no
manual steps.

The image starts from the official Debian cloud image and installs proxmox-ve
on top of it, rather than capturing a raw disk from the Proxmox ISO. That keeps
MAAS in control of partitioning, networking, SSH keys and cloud-init, and makes
moving between Proxmox releases a variable change instead of a rewrite.

Contents:

  * Makefile driving the whole flow: build, verify, preseed, upload
  * customize-proxmox.sh, run inside the Packer build VM, which layers Proxmox
    onto the Debian cloud image and resets the pmxcfs node identity so one image
    can produce many nodes
  * pve-maas-init, a first-boot state machine covering /etc/hosts, node-unique
    identifiers, the root password, vmbr0 conversion, cluster create/join and
    the local-lvm thin pool; each stage is resumable across reboots
  * curtin-hooks, which stops curtin installing a kernel over APT and pins
    interface names by MAC so they match what MAAS recorded at commissioning
  * a MAAS curtin preseed template and cloud-init examples
  * deploy-cluster.sh, which builds a whole cluster through the MAAS API
  * verify-image.sh, 22 static checks on the produced tarball

Cluster identity lives entirely in deploy-time cloud-init user-data, so a single
image and preseed can build any number of independent clusters.

Verified end to end against MAAS 3.7.2: proxmox-ve 9.2.0 / pve-manager 9.2.11 /
kernel 7.0.14-15-pve, deployed to two machines that formed a quorate cluster with
local-lvm on both, with no manual intervention.

The README documents four failure modes found along the way that all fail
silently: curtin rejecting "kernel: null", pvenetcommit overwriting the network
configuration at boot, interface renaming leaving the link down, and a systemd
ordering cycle that made systemd delete the service's start job.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

overlay/etc/pve-maas/pve-maas.conf

@@ -0,0 +1,98 @@
+# /etc/pve-maas/pve-maas.conf
+#
+# pve-maas-init varsayilan yapilandirmasi. BU DOSYAYI DUZENLEMEYIN.
+# Dugume ozel ayarlari MAAS deploy sirasinda cloud-init ile
+# /etc/pve-maas/conf.d/*.conf altina yazin; oradaki degerler bunlari ezer.
+#
+# Ornek (cloud-init user-data):
+#   write_files:
+#     - path: /etc/pve-maas/conf.d/50-cluster.conf
+#       permissions: "0600"
+#       content: |
+#         PVE_ROOT_PASSWORD='...'
+#         PVE_CLUSTER_MODE=join
+#         PVE_CLUSTER_PEER=192.0.2.11
+#         PVE_CLUSTER_PEER_PASSWORD='...'
+
+# ---------------------------------------------------------------- genel
+# Tum ilk acilis otomasyonunu kapatmak icin false yapin.
+PVE_ENABLED=true
+
+# Bos birakilirsa hostname -f / resolv.conf'tan turetilir.
+PVE_FQDN=
+
+# ---------------------------------------------------------------- ag
+# MAAS'in yapilandirdigi arayuz vmbr0 koprusune donusturulsun mu?
+# Bond/VLAN gibi karmasik topolojilerde false yapip /etc/network/interfaces
+# dosyasini cloud-init ile kendiniz yazin.
+PVE_NET_MANAGE=true
+
+PVE_NET_BRIDGE=vmbr0
+
+# Bos ise varsayilan rotayi tasiyan arayuz kullanilir.
+PVE_NET_UPLINK=
+
+# auto | static | dhcp   (auto: MAAS'in yazdigi yapilandirmadan tespit edilir)
+PVE_NET_MODE=auto
+
+# reboot | reload | none
+#   reboot : yapilandirmayi yazip bir kez yeniden baslatir (en guvenilir)
+#   reload : ifreload -a ile canli uygular (yeniden baslatma yok)
+#   none   : sadece yazar, uygulamaz
+PVE_NET_APPLY=reboot
+
+# Koprude VLAN farkindaligi (bridge-vlan-aware yes, vids 2-4094)
+PVE_NET_VLAN_AWARE=false
+
+# /etc/network/interfaces sonuna eklenecek ham metin (ek kopruler vb.)
+PVE_NET_EXTRA=
+
+# ---------------------------------------------------------------- root parolasi
+# root@pam web arayuzu girisi ve baska dugumlerin bu dugume katilmasi icin gerekli.
+# Duz metin yerine hash tercih edin:  openssl passwd -6
+PVE_ROOT_PASSWORD=
+PVE_ROOT_PASSWORD_HASH=
+
+# ---------------------------------------------------------------- kume
+# none | create | join
+PVE_CLUSTER_MODE=none
+
+# create icin
+PVE_CLUSTER_NAME=
+
+# join icin: mevcut bir kume dugumunun IP/hostname'i ve root@pam parolasi
+PVE_CLUSTER_PEER=
+PVE_CLUSTER_PEER_PASSWORD=
+PVE_CLUSTER_PEER_PASSWORD_FILE=
+
+# Sertifika parmak izi. Bos ve DISCOVER=true ise dugumden okunur (TOFU).
+# Guvenlik icin degeri onceden vermeniz onerilir:
+#   openssl s_client -connect NODE:8006 </dev/null 2>/dev/null | \
+#     openssl x509 -noout -fingerprint -sha256 | cut -d= -f2
+PVE_CLUSTER_FINGERPRINT=
+PVE_CLUSTER_FINGERPRINT_DISCOVER=true
+
+# Corosync baglantilari (ayri bir kume agi kullaniyorsaniz)
+PVE_CLUSTER_LINK0=
+PVE_CLUSTER_LINK1=
+PVE_CLUSTER_NODEID=
+PVE_CLUSTER_VOTES=
+
+# Kume dugumunun erisilebilir olmasi icin beklenecek sure (saniye) ve deneme sayisi
+PVE_CLUSTER_WAIT=900
+PVE_CLUSTER_RETRIES=5
+
+# Katilimdan sonra conf.d icindeki parolalari sil
+PVE_CLUSTER_WIPE_SECRETS=true
+
+# ---------------------------------------------------------------- depolama
+# auto | off | <vg-adi>
+#   auto: en cok bos alani olan VG secilir
+PVE_THINPOOL=auto
+PVE_THINPOOL_NAME=data
+PVE_THINPOOL_STORAGE=local-lvm
+PVE_THINPOOL_MIN_GB=16
+
+# Ayri bir disk verilirse o diskten yeni bir VG olusturulur.
+PVE_THINPOOL_DISK=
+PVE_THINPOOL_VG=pve