proxy1     cluster1     STALE        SYNCED      SYNCED      NOT SENT     SYNCED       istiod1     1.20
proxy2     cluster2     STALE        SYNCED      STALE       SYNCED       STALE        istiod2     1.19
proxy3     cluster3     NOT SENT     ERROR       STALE       NOT SENT     NOT SENT     istiod3     1.20

						clusterID:      "cluster2",
						version:        "1.19",
						cdsSyncStatus:  status.ConfigStatus_STALE,
						ldsSyncStatus:  status.ConfigStatus_SYNCED,
						rdsSyncStatus:  status.ConfigStatus_SYNCED,
						edsSyncStatus:  status.ConfigStatus_STALE,
						ecdsSyncStatus: status.ConfigStatus_STALE,
					},
				}),
				"istiod3": xdsResponseInput("istiod3", []clientConfigInput{
					{
						proxyID:        "proxy3",

	stales := actual.DifferenceInPlace(expected)

	for staleIP := range stales {
		if err := hostsideProbeSet.ClearEntriesWithIP(staleIP); err != nil {
			return err
		}
		log.Debugf("removed stale ip %s from host ipset %s", staleIP, hostsideProbeSet.Prefix)
	}
	return nil

	PodDeleted(ctx context.Context, uid string) error
	PodAdded(ctx context.Context, pod *v1.Pod, netns Netns) error
	Close() error
}

/*
To clean up stale ztunnels

	we may need to ztunnel to send its (uid, bootid / boot time) to us
	so that we can remove stale entries when the ztunnel pod is deleted
	or when the ztunnel pod is restarted in the same pod (remove old entries when the same uid connects again, but with different boot id?)

NAME       CLUSTER      CDS       LDS        EDS        RDS          ECDS         ISTIOD      VERSION
proxy1     cluster1     STALE     SYNCED     SYNCED     NOT SENT     NOT SENT     istiod1     1.20

						dr, _ = configClient.NetworkingV1alpha3().DestinationRules(drNamespace).Get(context.Background(), drName, metav1.GetOptions{})
						if dr == nil {
							fmt.Fprintf(writer,
								"WARNING: Proxy is stale; it references to non-existent destination rule %s.%s\n",
								drName, drNamespace)
						}
						recordDestinationRules[newResourceID(drNamespace, drName)] = dr.DeepCopy()
					}
				}
				if dr != nil {

  repeated APIResourceDiscovery resources = 2;

  // freshness marks whether a group version's discovery document is up to date.
  // "Current" indicates the discovery document was recently
  // refreshed. "Stale" indicates the discovery document could not
  // be retrieved and the returned discovery document may be
  // significantly out of date. Clients that require the latest
  // version of the discovery information be retrieved before