From aaa341b6b2012596e1402abd153852af60b183c0 Mon Sep 17 00:00:00 2001
From: Jason O'Brien <jasonobrien@google.com>
Date: Mon, 5 Oct 2026 01:16:45 -0500
Subject: [PATCH] monitor-all: read container IP from the host side (#17686)

The CT check resolved the IP by running ip inside the guest via pct
exec, which depends on the guest having it installed. If not, this
always comes back empty, so the container is restarted every cycle
despite answering ping. lxc-info reports the addresses from the
host without running anything inside the guest.

Fixes #17685
---
 tools/pve/monitor-all.sh | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/tools/pve/monitor-all.sh b/tools/pve/monitor-all.sh
index 650c86a8b..d1084aea4 100644
--- a/tools/pve/monitor-all.sh
+++ b/tools/pve/monitor-all.sh
@@ -110,8 +110,9 @@ while true; do
         pct start "$instance" >/dev/null 2>&1
         continue
       fi
-      # Not every container names its interface eth0.
-      IP=$(pct exec "$instance" -- ip -4 -o addr show scope global 2>/dev/null | awk '{print $4}' | cut -d/ -f1 | head -n1)
+      # Read the IP from the host side; pct exec depends on tools inside the
+      # guest, which minimal/OCI images may lack.
+      IP=$(lxc-info -n "$instance" -iH 2>/dev/null | awk '/^[0-9.]+$/ && !/^(127|169\.254)\./ {print; exit}')
       if [ -z "$IP" ] || ! ping -c 1 -W 2 "$IP" >/dev/null 2>&1; then
         echo "$(date): CT $instance is not responding, restarting..."
         pct stop "$instance" >/dev/null 2>&1