Network & RPC Configuration

ChronoLog includes built-in scripts installed under tools/ under the installation directory to help deploy ChronoLog in both local and distributed setups. The remaining sections on this page describe manual network and RPC configuration.

ChronoLog uses Thallium (a Mochi RPC framework built on Mercury) for all inter-component communication. Every service endpoint in the configuration follows the same rpc block structure.

RPC Block Structure

Each service in default_conf.json contains an rpc sub-block:

"SomeService": {
  "rpc": {
    "protocol_conf": "ofi+sockets",
    "service_ip": "127.0.0.1",
    "service_base_port": 5555,
    "service_provider_id": 55
  }
}

Field	Description
protocol_conf	Thallium/Mercury transport string. Controls the network layer used for RPC.
service_ip	IP address this service binds to (servers) or connects to (clients).
service_base_port	TCP/UDP port number for the service.
service_provider_id	Thallium provider ID, used to multiplex multiple services on the same address. Must be unique per address.

Protocol Options

The transport is set via protocol_conf. The three supported values correspond to the ChronoLogRPCImplementation enum:

protocol_conf value	Enum constant	Use case
"ofi+sockets"	CHRONOLOG_THALLIUM_SOCKETS (0)	TCP sockets via libfabric. Works everywhere, no special hardware required. Recommended for development and single-node testing.
"ofi+verbs"	CHRONOLOG_THALLIUM_TCP (1)	InfiniBand Verbs via libfabric. Requires InfiniBand hardware. Use on HPC clusters with IB interconnects.
"ofi+roce"	CHRONOLOG_THALLIUM_ROCE (2)	RDMA over Converged Ethernet. Requires RoCE-capable NICs. Use for high-performance Ethernet deployments.

note

All components in a deployment must use the same protocol_conf. Mixing transports is not supported.

Default Port Assignments

The table below lists the default ports for every service across all ChronoLog components. These must be consistent between the component that listens on a port and the component that connects to it.

Component	Service	Default Port	Provider ID	Connects from
ChronoVisor	VisorClientPortalService	5555	55	ChronoClient
ChronoVisor	VisorKeeperRegistryService	8888	88	ChronoKeeper, ChronoGrapher, ChronoPlayer
ChronoKeeper	KeeperRecordingService	6666	66	ChronoVisor (event routing)
ChronoKeeper	KeeperDataStoreAdminService	7777	77	ChronoVisor (admin)
ChronoKeeper	KeeperGrapherDrainService	3333	33	ChronoGrapher
ChronoGrapher	KeeperGrapherDrainService	3333	33	ChronoKeeper
ChronoGrapher	DataStoreAdminService	4444	44	ChronoVisor (admin)
ChronoPlayer	PlayerStoreAdminService	2222	22	ChronoVisor (admin)
ChronoPlayer	PlaybackQueryService	2225	25	ChronoClient (queries)
ChronoClient	VisorClientPortalService	5555	55	→ ChronoVisor
ChronoClient	ClientQueryService	5557	57	← ChronoPlayer (responses)

Multi-Node Setup

In single-node deployments, every service_ip defaults to 127.0.0.1. For distributed deployments, each component's service_ip must be set to the actual IP address of the host it runs on.

Example: three-node deployment

Host	IP	Components
node01	10.0.0.1	ChronoVisor
node02	10.0.0.2	ChronoKeeper + ChronoGrapher
node03	10.0.0.3	ChronoPlayer

On node01 (chrono_visor block):

"VisorClientPortalService": {
  "rpc": { "service_ip": "10.0.0.1", "service_base_port": 5555, ... }
},
"VisorKeeperRegistryService": {
  "rpc": { "service_ip": "10.0.0.1", "service_base_port": 8888, ... }
}

On node02 (chrono_keeper and chrono_grapher blocks), the VisorKeeperRegistryService entry points to the visor:

"VisorKeeperRegistryService": {
  "rpc": { "service_ip": "10.0.0.1", "service_base_port": 8888, ... }
},
"KeeperRecordingService": {
  "rpc": { "service_ip": "10.0.0.2", "service_base_port": 6666, ... }
}

On the client host, VisorClientPortalService.service_ip must point to node01:

"VisorClientPortalService": {
  "rpc": { "service_ip": "10.0.0.1", "service_base_port": 5555, ... }
}

Firewall: ensure all ports listed in the table above are open between the relevant hosts. For ofi+sockets, all communication is TCP; the port numbers are exactly the service_base_port values.