Skip to content


Pantheon uses the network to find and connect to peers.

Port Configuration

Ports must be exposed appropriately to enable communication. An example port configuration for a Pantheon node on AWS is:

Port Configuration

P2P Networking

To enable peer discovery, the P2P UDP port must be open for inbound connections.

We also recommended opening the P2P TCP port for inbound connections. This is not strictly required because Pantheon attempts to initiate outbound TCP connections. However, if no nodes on the network are accepting inbound TCP connections, nodes cannot communicate.

The P2P port is specified by the --p2p-port option. The default is 30303.


To enable access to the JSON-RPC API, open the HTTP JSON-RPC and WebSockets JSON-RPC ports to the intended users of the JSON-RPC API on TCP.

The --rpc-http-port and --rpc-ws-port options specify the HTTP and WebSockets JSON-RPC ports. The defaults are 8545 and 8546.


To enable Prometheus to access Pantheon, open the metrics port or metrics push port to Prometheus or the Prometheus push gateway on TCP.

The --metrics-port and --metrics-push-port options specify the ports for Prometheus and Prometheus push gateway. The defaults are 9545 and 9001.

Node Connections

The default logging configuration does not list node connection and disconnection messages.

To enable listing of node connection and disconnection messages, specify the --logging command line option --logging=DEBUG. For more verbosity, specify --logging=TRACE.

The console logs connection and disconnection events when the log level is DEBUG or higher.
If Successfully accepted connection from ... is displayed, connections are getting through the firewalls.

Example log output

2018-10-16 12:37:35.479-04:00 | nioEventLoopGroup-3-1 | INFO | NettyP2PNetwork | Successfully accepted connection from 0xa979fb575495b8d6db44f750317d0f4622bf4c2aa3365d6af7c284339968eef29b69ad0dce72a4d8db5ebb4968de0e3bec910127f134779fbcb0cb6d3331163c

Limiting Peers

Limiting peers reduces the bandwidth used by Pantheon. It also reduces the CPU time and disk access used to manage and respond to peers.

Use the --max-peers command line option to reduce the maximum number of peers. The default is 25.

No Discovery

The --discovery-enabled command line option can be used to disable P2P peer discovery. Set this option to false if you are running a test node or a test network with fixed nodes.

Use the admin_addPeer JSON-RPC method to add peers when --discovery-enabled is set to false.

Monitoring Peer Connections

Use the debug_metrics JSON-RPC API method to obtain information about peer connections.

Questions or feedback? You can discuss issues and obtain free support on Pegasys Pantheon Gitter room.
For paid professional support by PegaSys, contact us at [email protected]