From 0beaf2f1f2d21712b47360547a54bbdd5e8ff13b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C3=A9r=C3=B4me=20Petazzoni?= <jerome.petazzoni@gmail.com>
Date: Mon, 17 Nov 2025 15:31:25 +0100
Subject: [PATCH] =?UTF-8?q?=F0=9F=9B=9C=20Generate=20HAProxy=20configurati?=
 =?UTF-8?q?on=20for=20Proxmox=20IPv6=20scenario?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../virtual-machines/proxmox/haproxy.tf       | 37 +++++++++++++++++++
 .../virtual-machines/proxmox/main.tf          |  1 -
 .../virtual-machines/proxmox/tfvars.example   |  7 +++-
 3 files changed, 42 insertions(+), 3 deletions(-)
 create mode 100644 prepare-labs/terraform/virtual-machines/proxmox/haproxy.tf

diff --git a/prepare-labs/terraform/virtual-machines/proxmox/haproxy.tf b/prepare-labs/terraform/virtual-machines/proxmox/haproxy.tf
new file mode 100644
index 00000000..5255af74
--- /dev/null
+++ b/prepare-labs/terraform/virtual-machines/proxmox/haproxy.tf
@@ -0,0 +1,37 @@
+# If we deploy in IPv6-only environments, and the students don't have IPv6
+# connectivity, we want to offer a way to connect anyway. Our solution is
+# to generate an HAProxy configuration snippet, that can be copied to a
+# DualStack machine which will act as a proxy to our IPv6 machines.
+# Note that the snippet still has to be copied, so this is not a 100%
+# streamlined solution!
+
+locals {
+  portmaps = {
+    for key, value in local.nodes :
+    (10000 + proxmox_virtual_environment_vm._[key].vm_id) => local.ip_addresses[key]
+  }
+}
+
+resource "local_file" "haproxy" {
+  filename        = "./${var.tag}.cfg"
+  file_permission = "0644"
+  content = join("\n", [for port, address in local.portmaps : <<-EOT
+  frontend f${port}
+    bind *:${port}
+    default_backend b${port}
+  backend b${port}
+    mode tcp
+    server s${port} [${address}]:22 maxconn 16
+  EOT
+  ])
+}
+
+resource "local_file" "sshproxy" {
+  filename        = "sshproxy.txt"
+  file_permission = "0644"
+  content = join("", [
+    for cid in range(1, 1 + var.how_many_clusters) :
+    format("ssh -l k8s -p %d\n", proxmox_virtual_environment_vm._[format("c%03dn%03d", cid, 1)].vm_id + 10000)
+  ])
+}
+
diff --git a/prepare-labs/terraform/virtual-machines/proxmox/main.tf b/prepare-labs/terraform/virtual-machines/proxmox/main.tf
index a978b5f1..b141ee30 100644
--- a/prepare-labs/terraform/virtual-machines/proxmox/main.tf
+++ b/prepare-labs/terraform/virtual-machines/proxmox/main.tf
@@ -111,4 +111,3 @@ locals {
     addr if addr != "127.0.0.1" && addr != "::1"][0]
   }
 }
-
diff --git a/prepare-labs/terraform/virtual-machines/proxmox/tfvars.example b/prepare-labs/terraform/virtual-machines/proxmox/tfvars.example
index 837b9826..ed4cf5f8 100644
--- a/prepare-labs/terraform/virtual-machines/proxmox/tfvars.example
+++ b/prepare-labs/terraform/virtual-machines/proxmox/tfvars.example
@@ -10,8 +10,11 @@ proxmox_password = "CHANGEME"
 
 # Which storage to use for VM disks. Defaults to "local".
 #proxmox_storage = "ceph"
+#proxmox_storage = "local-zfs"
 
-proxmox_template_node_name = "CHANGEME"
-proxmox_template_vm_id = CHANGEME
+# We recently rewrote the Proxmox configurations to automatically
+# detect which template to use; so these variables aren't used anymore.
+#proxmox_template_node_name = "CHANGEME"
+#proxmox_template_vm_id = CHANGEME