From 7ebf94cc2316dc34be31cbe1064b75ff9b4a15b7 Mon Sep 17 00:00:00 2001
From: Stefan Bethke <stb@lassitu.de>
Date: Tue, 31 Mar 2026 19:55:02 +0200
Subject: [PATCH] Install a one-shot service to initialize hostid

---
 build-proxmox-template     |  9 +++++++--
 initialize-host-id         |  8 ++++++++
 initialize-host-id.service | 13 +++++++++++++
 3 files changed, 28 insertions(+), 2 deletions(-)
 create mode 100644 initialize-host-id
 create mode 100644 initialize-host-id.service

diff --git a/build-proxmox-template b/build-proxmox-template
index e97a758..d3bb232 100755
--- a/build-proxmox-template
+++ b/build-proxmox-template
@@ -9,12 +9,13 @@
 : "${STORAGE:=local-zfs}"
 : "${OS:=debian-13}"
 : "${NAME:=chaos-${OS}-tmpl-$(date -u +%Y-%m-%d)}"
-: "${BRIDGE:=vmbr0,tag=208}"
+: "${BRIDGE:=vmbr0,tag=2}"
 : "${AUTHORIZED_KEYS_URL:=https://git.hamburg.ccc.de/CCCHH/infrastructure-authorized-keys/raw/branch/trunk/authorized_keys}"
 
 set -eE
 
 export PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:$PATH
+here="$(pwd)"
 
 tempfolder=$(mktemp -d /tmp/cloudinit-XXXXX)
 pushd $tempfolder
@@ -44,7 +45,11 @@ virt-customize -a disk.raw \
 	--uninstall openipmi \
 	--run-command 'systemctl enable qemu-guest-agent' \
 	--run-command 'systemctl enable fstrim.timer' \
-	--run-command 'echo -n >/etc/machine-id'
+	--run-command 'echo -n >/etc/machine-id' \
+	--copy-in ${here}/initialize-host-id:/usr/local/sbin \
+	--run-command 'chmod +x /usr/local/sbin/initialize-host-id' \
+	--copy-in ${here}/initialize-host-id.service:/etc/systemd/system \
+	--run-command 'systemctl enable initialize-host-id.service'
 
 qm destroy ${VMID} || true
 qm create ${VMID} --name "creating-vm" --memory 2048 --net0 virtio,bridge=${BRIDGE}
diff --git a/initialize-host-id b/initialize-host-id
new file mode 100644
index 0000000..c45255d
--- /dev/null
+++ b/initialize-host-id
@@ -0,0 +1,8 @@
+#!/bin/sh
+
+#
+# Initialize /etc/hostid if it doesn't exist or is empty
+#
+if [ ! -f /etc/hostid -o "$(cat /etc/hostid 2>/dev/null)" = "" ]; then
+    hexdump -n 4 -e '"%02x"' /dev/urandom >/etc/hostid
+fi
diff --git a/initialize-host-id.service b/initialize-host-id.service
new file mode 100644
index 0000000..e7cdfa3
--- /dev/null
+++ b/initialize-host-id.service
@@ -0,0 +1,13 @@
+[Unit]
+Description=Initialize /etc/hostid
+Documentation=https://git.hamburg.ccc.de/CCCHH/pve-template-vm
+After=sysinit.target
+
+[Service]
+Type=oneshot
+ExecStart=/usr/local/sbin/initialize-host-id
+User=root
+Restart=never
+
+[Install]
+WantedBy=sysinit.target