From af19ebc4de0906b7b7824fecc6df655a0a5f1691 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Felix=20Bu=CC=88nemann?= <felix.buenemann@gmail.com>
Date: Wed, 16 Jul 2025 23:07:56 +0200
Subject: [PATCH] Allow monitor node binary upgrades with pg_upgrade

by skipping extension startup if a binary upgrade is detected.

Without this fix pg_upgrade will hang trying to drop in-use databases in
the newly created (supposed to be) empty cluster.
---
 src/monitor/pg_auto_failover.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/src/monitor/pg_auto_failover.c b/src/monitor/pg_auto_failover.c
index c780a8fd4..3646ae3ef 100644
--- a/src/monitor/pg_auto_failover.c
+++ b/src/monitor/pg_auto_failover.c
@@ -75,6 +75,15 @@ PG_MODULE_MAGIC;
 void
 _PG_init(void)
 {
+	/* Check PostgreSQL's internal binary upgrade flag */
+	extern bool IsBinaryUpgrade;
+	if (IsBinaryUpgrade)
+	{
+		ereport(LOG,
+				(errmsg("pgautofailover: skipping initialization during binary upgrade")));
+		return;
+	}
+
 	if (!process_shared_preload_libraries_in_progress)
 	{
 		ereport(ERROR,