One of the benefits of Memcached is that it allows you to spread caching load across multiple servers. From looking at the config file for Calendar Server, it looked initially to me that it would support multiple Memcached servers, but now I guess I'm not so sure. This is how php handles multi-server configuration: $MEMCACHE_SERVERS = array( "10.1.1.1", //web1 "10.1.1.2", //web2 "10.1.1.3", //web3 ); I did a quick search of the code and I think I've found the connection method for memcache. I found this in txdav/who/cache.py so let me know if I've gone to the wrong place. It looks like it is only able to handle one server (hightlighted below). Am I missing some secret method to allow for multi-server memcached? def _getMemcacheClient(self, refresh=False): """ Get the memcache client instance to use for caching. @param refresh: whether or not to create a new memcache client @type refresh: L{bool} @return: the client to use @rtype: L{memcacheclient.Client} """ if refresh or not hasattr(self, "memcacheClient"): if config.Memcached.Pools.Default.MemcacheSocket: client_addr = "unix:{}".format(config.Memcached.Pools.Default.MemcacheSocket) else: client_addr = "{}:{}".format( config.Memcached.Pools.Default.BindAddress, config.Memcached.Pools.Default.Port, ) self.memcacheClient = ClientFactory.getClient([client_addr], debug=0, pickleProtocol=2) return self.memcacheClient