code: public void setFailoverNodes( final String failoverNodes ) {
          if ( _manager.isInitialized() ) {
              final MemcachedNodesManager config = reloadMemcachedConfig( _memcachedNodes, failoverNodes );
              _log.info( "Loaded new memcached failover node configuration." +
                      "\n- Former failover config: "+ _failoverNodes +
                      "\n- New failover config: " + failoverNodes +
                      "\n- New node ids: " + config.getPrimaryNodeIds() +
                      "\n- New failover node ids: " + config.getFailoverNodeIds() );
          }
          _failoverNodes = failoverNodes;
      }
docs: The node ids of memcached nodes, that shall only be used for session
  backup by this tomcat/manager, if there are no other memcached nodes
  left. Node ids are separated by whitespace or comma.
  <p>
  E.g. <code>n1 n2</code>
  </p>
  <p>
  When the failover nodes are set when this manager is already initialized,
  the new configuration will be loaded.
  </p>
  
  @param failoverNodes
  the failoverNodes to set, whitespace or comma separated