change, rather than reliably updating every 60 seconds (or whatever). If you
  are trying to monitor for whether iptables updates are failing, the
  `sync_proxy_rules_iptables_restore_failures_total` metric may be more useful. ([#81517](https://github.com/kubernetes/kubernetes/pull/81517), [@danwinship](https://github.com/danwinship))
### Instrumentation