fix: print IM pod log when state is error

Signed-off-by: Shuo Wu <shuo.wu@suse.com>

Author: shuo-wu

controller/instance_manager_controller.go

@@ -491,6 +491,12 @@ func (imc *InstanceManagerController) syncStatusWithPod(im *longhorn.InstanceMan
 		}
 	default:
 		imc.logger.Warnf("Instance manager pod %v is in phase %s, updating the instance manager state from %s to error", im.Name, pod.Status.Phase, im.Status.CurrentState)
+
+		if podLog, err := imc.ds.GetPodContainerLog(im.Name, "instance-manager"); err != nil {
+			log.WithError(err).Warnf("Failed to get pod log for instance manager %v", im.Name)
+		} else {
+			log.Warnf("Instance manager pod %v is in phase %s, pod log: %s", im.Name, pod.Status.Phase, string(podLog))
+		}
 		im.Status.CurrentState = longhorn.InstanceManagerStateError
 	}