if filter.Direction != "outbound" {
			for _, c := range wl.Connections.Inbound {
				fmt.Fprintf(w, "%v\tInbound\t%v\t%v\t%v\n", name, lookupIP(c.ActualDst), lookupIP(c.Src), c.OriginalDst)
			}
		}
		if filter.Direction != "inbound" {
			for _, c := range wl.Connections.Outbound {

*/

type connMgr struct {
	connectionSet map[*ZtunnelConnection]struct{}
	latestConn    *ZtunnelConnection
	mu            sync.Mutex
}

func (c *connMgr) addConn(conn *ZtunnelConnection) {
	log.Debug("ztunnel connected")
	c.mu.Lock()
	defer c.mu.Unlock()
	c.connectionSet[conn] = struct{}{}
	c.latestConn = conn
	ztunnelConnected.RecordInt(int64(len(c.connectionSet)))
}

Realistically, that means the best we can do is:
* Ensure that, at any point in time, any _new_ connections will succeed. There is no period where new connections are dropped.
* Provide some period of time for the old Ztunnel to continue processing any established connections.

If this period of time ("drain period") is longer than any connections, there is zero impact on applications at all.

var globalLockGrid atomic.Pointer[grid.Manager]

// globalGridStart is a channel that will block startup of grid connections until closed.
var globalGridStart = make(chan struct{})

// globalLockGridStart is a channel that will block startup of lock grid connections until closed.
var globalLockGridStart = make(chan struct{})

func initGlobalGrid(ctx context.Context, eps EndpointServerPools) error {

      panels.timeSeries.base('CPU Usage', queries.cpuUsage, 'CPU usage of each running instance'),
    ]),
    row.new('Network')
    + row.withPanels([
      panels.timeSeries.connections('Connections', queries.connections, 'Connections opened and closed per instance'),
      panels.timeSeries.bytesRate('Bytes Transmitted', queries.bytes, 'Bytes sent and received per instance'),

  }

  // Node/edge sets are the same, but node/edge connections differ due to edge type.
  @Test
  public void equivalent_directedVsUndirected() {
    graph.putEdge(N1, N2);

    MutableGraph<Integer> g2 = createGraph(oppositeType(edgeType));
    g2.putEdge(N1, N2);

    assertThat(graph).isNotEqualTo(g2);
  }

  // Node/edge sets and node/edge connections are the same, but directedness differs.
  @Test

  }

  // Node/edge sets are the same, but node/edge connections differ due to edge type.
  @Test
  public void equivalent_directedVsUndirected() {
    graph.putEdge(N1, N2);

    MutableGraph<Integer> g2 = createGraph(oppositeType(edgeType));
    g2.putEdge(N1, N2);

    assertThat(graph).isNotEqualTo(g2);
  }

  // Node/edge sets and node/edge connections are the same, but directedness differs.
  @Test

  // Node/edge sets are the same, but node/edge connections differ due to edge type.
  @Test
  public void equivalent_directedVsUndirected() {
    network.addEdge(N1, N2, E12);

    MutableNetwork<Integer, String> g2 = createNetwork(oppositeType(edgeType));
    g2.addEdge(N1, N2, E12);

    assertThat(network).isNotEqualTo(g2);
  }

  // Node/edge sets and node/edge connections are the same, but directedness differs.
  @Test

  // Node/edge sets are the same, but node/edge connections differ due to edge type.
  @Test
  public void equivalent_directedVsUndirected() {
    network.addEdge(N1, N2, E12);

    MutableNetwork<Integer, String> g2 = createNetwork(oppositeType(edgeType));
    g2.addEdge(N1, N2, E12);

    assertThat(network).isNotEqualTo(g2);
  }

  // Node/edge sets and node/edge connections are the same, but directedness differs.
  @Test

      ),
      panels.timeSeries.base(
        'Events', queries.pilotEvents, |||
          Size of each xDS push.
        |||
      ),
      panels.timeSeries.base(
        'Connections', queries.xdsConnections, |||
          Total number of XDS connections
        |||
      ),
      panels.timeSeries.base(
        'Push Errors', queries.xdsErrors, |||