void shutdown() {
        log.log(Level.INFO, "Triggering shutdown");
        server.shutdown();
        executorService.shutdownNow();
        try {
            if (!executorService.awaitTermination(STOP_TIMEOUT.toMillis(), TimeUnit.MILLISECONDS)) {
                log.log(Level.WARNING, "Failed to shut down within " + STOP_TIMEOUT);
            }
        } catch (InterruptedException e) {
            log.log(Level.WARNING, "Interrupted waiting for executor to complete", e);
        }
    }
Writes zookeeper config and starts zookeeper server.

@author Harald Musum
zookeeper-server/zookeeper-server-common/src/main/java/com/yahoo/vespa/zookeeper/ZooKeeperRunner.java