Description of configuration options for zmq

Configuration option = Default value	Description
[DEFAULT]
rpc_cast_timeout = 30	(IntOpt) Seconds to wait before a cast expires (TTL). Only supported by impl_zmq.
rpc_zmq_bind_address = *	(StrOpt) ZeroMQ bind address. Should be a wildcard (*), an ethernet interface, or IP. The "host" option should point or resolve to this address.
rpc_zmq_contexts = 1	(IntOpt) Number of ZeroMQ contexts, defaults to 1.
rpc_zmq_host = localhost	(StrOpt) Name of this node. Must be a valid hostname, FQDN, or IP address. Must match "host" option, if running Nova.
rpc_zmq_ipc_dir = /var/run/openstack	(StrOpt) Directory for holding IPC sockets.
rpc_zmq_matchmaker = oslo.messaging._drivers.matchmaker.MatchMakerLocalhost	(StrOpt) MatchMaker driver.
rpc_zmq_port = 9501	(IntOpt) ZeroMQ receiver listening port.
rpc_zmq_topic_backlog = None	(IntOpt) Maximum number of ingress messages to locally buffer per topic. Default is unlimited.