From cf577e715fbcc398b4e5f574becaeb630f2114de Mon Sep 17 00:00:00 2001
From: rcourtman <courtmanr@gmail.com>
Date: Fri, 26 Dec 2025 17:52:32 +0000
Subject: [PATCH] fix: Clear node host agent link when agent is removed

When a host agent is deleted via the UI, the LinkedHostAgentID on any
PVE nodes that were linked to it was not being cleared. This caused
the "Agent" tag to persist in the UI after uninstalling the agent.

Related to #920
---
 internal/models/models.go      | 19 +++++++++++++++++++
 internal/monitoring/monitor.go |  9 +++++++++
 2 files changed, 28 insertions(+)

diff --git a/internal/models/models.go b/internal/models/models.go
index 110f9fb2f..ad05e92e2 100644
--- a/internal/models/models.go
+++ b/internal/models/models.go
@@ -2029,6 +2029,25 @@ func (s *State) LinkNodeToHostAgent(nodeID, hostAgentID string) bool {
 	return false
 }
 
+// UnlinkNodesFromHostAgent clears LinkedHostAgentID from all nodes linked to the given host agent.
+// This is called when a host agent is removed to clean up stale references.
+func (s *State) UnlinkNodesFromHostAgent(hostAgentID string) int {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	count := 0
+	for i, node := range s.Nodes {
+		if node.LinkedHostAgentID == hostAgentID {
+			s.Nodes[i].LinkedHostAgentID = ""
+			count++
+		}
+	}
+	if count > 0 {
+		s.LastUpdate = time.Now()
+	}
+	return count
+}
+
 // UpsertCephCluster inserts or updates a Ceph cluster in the state.
 // Uses ID (typically the FSID) for matching.
 func (s *State) UpsertCephCluster(cluster CephCluster) {
diff --git a/internal/monitoring/monitor.go b/internal/monitoring/monitor.go
index f440f8272..7db302a28 100644
--- a/internal/monitoring/monitor.go
+++ b/internal/monitoring/monitor.go
@@ -1210,6 +1210,15 @@ func (m *Monitor) RemoveHostAgent(hostID string) (models.Host, error) {
 
 	m.state.RemoveConnectionHealth(hostConnectionPrefix + hostID)
 
+	// Clear LinkedHostAgentID from any nodes that were linked to this host agent
+	unlinkedCount := m.state.UnlinkNodesFromHostAgent(hostID)
+	if unlinkedCount > 0 {
+		log.Info().
+			Str("hostID", hostID).
+			Int("unlinkedNodes", unlinkedCount).
+			Msg("Cleared host agent links from PVE nodes")
+	}
+
 	log.Info().
 		Str("host", host.Hostname).
 		Str("hostID", hostID).