hosts = fmt.Sprintf("%s %s\n", ingressIP, IstiodHost(istioNamespace, revision))
	} else {
		log.Warnf("Could not auto-detect IP for %s/%s. Use --ingressIP to manually specify the Gateway address to reach istiod from the VM.",
			IstiodHost(istioNamespace, revision), istioNamespace)
	}
	return os.WriteFile(filepath.Join(dir, "hosts"), []byte(hosts), filePerms)
}

func isRevisioned(revision string) bool {

	// If needed, the remaining pieces of metadata can be added to the static env var (missing is the gce_* ones).
	if len(GCPStaticMetadata) != 0 {
		return GCPStaticMetadata
	}
	// If we cannot reach the metadata server, bail out with only statically defined metadata
	fillMetadata := e.shouldFillMetadata()
	if !fillMetadata {
		return nil
	}

	e.Lock()
	defer e.Unlock()

	// TODO(mathetake): have "Anonymous" option?
	if opt.useDefaultKeyChain() {
		// Note that default key chain reads the docker config from DOCKER_CONFIG
		// so must set the envvar when reaching this branch is expected.
		fetchOpts = append(fetchOpts, remote.WithAuthFromKeychain(authn.DefaultKeychain))
	} else {
		fetchOpts = append(fetchOpts, remote.WithAuthFromKeychain(&wasmKeyChain{data: opt.PullSecret}))
	}

  oneof destination {
    // TODO: add support for hostname lookup
    NamespacedHostname hostname = 1;
    NetworkAddress address = 2;
  }
  // port to reach the gateway at for mTLS HBONE connections
  uint32 hbone_mtls_port = 3;
  reserved "hbone_single_tls_port";
  reserved 4;
}

// NetworkAddress represents an address bound to a specific network.