Allow host role mismatch when resetting nodes if --force given

phase/gather_k0s_facts.go

@@ -342,7 +342,9 @@ func (p *GatherK0sFacts) investigateK0s(ctx context.Context, h *cluster.Host) er
 	}
 
 	if status.Role != h.Role {
-		return fmt.Errorf("%s: is configured as k0s %s but is already running as %s - role change is not supported", h, h.Role, status.Role)
+		if err := p.handleRoleMismatch(h, status.Role); err != nil {
+			return err
+		}
 	}
 
 	h.Metadata.K0sRunningVersion = status.Version
@@ -405,6 +407,20 @@ func (p *GatherK0sFacts) investigateK0s(ctx context.Context, h *cluster.Host) er
 	return nil
 }
 
+func (p *GatherK0sFacts) handleRoleMismatch(h *cluster.Host, detectedRole string) error {
+	if !h.Reset {
+		return fmt.Errorf("%s: is configured as k0s %s but is already running as %s - role change is not supported", h, h.Role, detectedRole)
+	}
+
+	if !Force {
+		return fmt.Errorf("%s: is configured as k0s %s but is already running as %s - role change is not supported, use --force to ignore the mismatch during reset", h, h.Role, detectedRole)
+	}
+
+	log.Warnf("%s: was configured as %s but is already running as %s - proceeding with reset using the discovered role because --force was given", h, h.Role, detectedRole)
+	h.Role = detectedRole
+	return nil
+}
+
 func (p *GatherK0sFacts) needsUpgrade(h *cluster.Host) bool {
 	if h.Reset {
 		return false

phase/gather_k0s_facts_test.go

@@ -70,3 +70,33 @@ func TestReportUseExistingHostsFailsWithoutBinary(t *testing.T) {
 	p.SetManager(mgr)
 	require.ErrorContains(t, p.reportUseExistingHosts(), "useExistingK0s=true but no k0s binary found on host")
 }
+
+func TestHandleRoleMismatch(t *testing.T) {
+	originalForce := Force
+	t.Cleanup(func() { Force = originalForce })
+
+	p := GatherK0sFacts{}
+
+	t.Run("host not marked for reset", func(t *testing.T) {
+		Force = true
+		h := &cluster.Host{Role: "controller"}
+		err := p.handleRoleMismatch(h, "worker")
+		require.ErrorContains(t, err, "role change is not supported")
+		require.Equal(t, "controller", h.Role)
+	})
+
+	t.Run("reset host requires force", func(t *testing.T) {
+		Force = false
+		h := &cluster.Host{Role: "controller", Reset: true}
+		err := p.handleRoleMismatch(h, "single")
+		require.ErrorContains(t, err, "use --force")
+		require.Equal(t, "controller", h.Role)
+	})
+
+	t.Run("force allows role update", func(t *testing.T) {
+		Force = true
+		h := &cluster.Host{Role: "controller", Reset: true}
+		require.NoError(t, p.handleRoleMismatch(h, "worker"))
+		require.Equal(t, "worker", h.Role)
+	})
+}