public void removeKeyFromZK(AuthenticationKey key) {
    String keyZNode = getKeyNode(key.getKeyId());
    try {
      ZKUtil.deleteNode(watcher, keyZNode);
    } catch (KeeperException.NoNodeException nne) {
      LOG.error("Non-existent znode " + keyZNode + " for key " + key.getKeyId(), nne);
    } catch (KeeperException ke) {
      LOG.error(HBaseMarkers.FATAL,
        "Failed removing znode " + keyZNode + " for key " + key.getKeyId(), ke);
      watcher.abort(
        "Unhandled zookeeper error removing znode " + keyZNode + " for key " + key.getKeyId(), ke);
    }
  }
Synchronizes token encryption keys across cluster nodes.
hbase-server/src/main/java/org/apache/hadoop/hbase/security/token/ZKSecretWatcher.java