From e4aeee9d85d3c093af609921be0eb71caa111470 Mon Sep 17 00:00:00 2001
From: Tom <CoMPaTech@users.noreply.github.com>
Date: Wed, 8 Apr 2026 13:22:25 +0200
Subject: [PATCH] Fix ProxmoxVE migration causing reauthentication (#167624)

---
 .../components/proxmoxve/__init__.py          |  8 ++++++
 tests/components/proxmoxve/test_init.py       | 27 +++++++++++++++++++
 2 files changed, 35 insertions(+)

diff --git a/homeassistant/components/proxmoxve/__init__.py b/homeassistant/components/proxmoxve/__init__.py
index 6512b1761cd9..3e680f212a2d 100644
--- a/homeassistant/components/proxmoxve/__init__.py
+++ b/homeassistant/components/proxmoxve/__init__.py
@@ -189,6 +189,14 @@ async def async_migrate_entry(hass: HomeAssistant, entry: ProxmoxConfigEntry) ->
     # Migration for additional configuration options added to support API tokens
     if entry.version < 3:
         data = dict(entry.data)
+        # If CONF_REALM wasn't there yet, extract from username
+        if CONF_REALM not in data:
+            data[CONF_REALM] = DEFAULT_REALM
+            if "@" in data.get(CONF_USERNAME, ""):
+                username, realm = data[CONF_USERNAME].split("@", 1)
+                data[CONF_USERNAME] = username
+                data[CONF_REALM] = realm.lower()
+
         realm = data[CONF_REALM].lower()
 
         # If the realm is one of the base providers, set the provider to match the realm.
diff --git a/tests/components/proxmoxve/test_init.py b/tests/components/proxmoxve/test_init.py
index 205e54f1e334..a3f7b21181ae 100644
--- a/tests/components/proxmoxve/test_init.py
+++ b/tests/components/proxmoxve/test_init.py
@@ -281,6 +281,33 @@ async def test_migration_v2_to_v3(
     assert entry.data[CONF_REALM] == AUTH_PAM
 
 
+async def test_migration_v2_to_v3_without_realm(
+    hass: HomeAssistant,
+) -> None:
+    """Test migration from version 2 to 3."""
+    entry = MockConfigEntry(
+        domain=DOMAIN,
+        version=2,
+        unique_id="1",
+        data={
+            CONF_HOST: "http://test_host",
+            CONF_PORT: 8006,
+            CONF_USERNAME: "test_user@pam",
+            CONF_PASSWORD: "test_password",
+            CONF_VERIFY_SSL: True,
+        },
+    )
+    entry.add_to_hass(hass)
+    assert entry.version == 2
+
+    await hass.config_entries.async_setup(entry.entry_id)
+    await hass.async_block_till_done()
+
+    assert entry.version == 3
+    assert entry.data[CONF_AUTH_METHOD] == AUTH_PAM
+    assert entry.data[CONF_REALM] == AUTH_PAM
+
+
 async def test_new_vm_creates_entity(
     hass: HomeAssistant,
     mock_proxmox_client: MagicMock,