@Override
    public String cancelInProgress() {
      DistributionManager dm = getDM();
      if (dm == null) {
        return "no distribution manager";
      }
      if (stopped) {
        return "Conduit has been stopped";
      }
      return null;
    }
Called by Connection before handshake reply is sent. Returns true if member is part of
view, false if membership is not confirmed before timeout.
geode-core/src/main/java/org/apache/geode/internal/tcp/TCPConduit.java