public RuntimeException generateCancelledException(Throwable e) {
      if (shutdownCause instanceof MemberDisconnectedException) {
        MembershipClosedException newException =
            new MembershipClosedException("membership shutdown",
                e);
        throw newException;
      }
      String reason = cancelInProgress();
      if (reason == null) {
        return null;
      } else {
        if (e == null) {
          return new MembershipClosedException(reason);
        } else {
          return new MembershipClosedException(reason, e);
        }
      }
    }
Start services - this will start everything up and join the cluster.
Invoke init() before this method.
geode-membership/src/main/java/org/apache/geode/distributed/internal/membership/gms/Services.java