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erigon-network-ports

DevOps & Security
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Reference for all Erigon network ports. Use this when running multiple Erigon instances to avoid port conflicts. Lists every CLI flag that binds a port, its default value, and the protocol used.

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Erigon Port Reference

When running multiple Erigon instances on the same machine, every listening port must be unique per instance. Erigon will fail at startup if any port is already in use, reporting bind: address already in use.

All Ports That Must Be Changed

CLI FlagDefaultProtocolDescription
--private.api.addr127.0.0.1:9090TCP (gRPC)Internal gRPC API for component communication (txpool, rpcdaemon, sentry, downloader)
--http.port8545TCPJSON-RPC HTTP server
--authrpc.port8551TCPEngine API (consensus layer auth RPC)
--ws.port8546TCPWebSocket RPC server
--torrent.port42069TCP+UDPBitTorrent protocol for snapshot downloads
--port30303TCP+UDPDevP2P network listening port (all eth versions multiplexed)
--caplin.discovery.port4000UDPCaplin consensus DISCV5 discovery
--caplin.discovery.tcpport4001TCPCaplin consensus DISCV5 TCP
--sentinel.port7777TCPSentinel (consensus p2p service)
--beacon.api.port5555TCPBeacon Chain REST API
--mcp.port8553TCPMCP (Model Context Protocol) RPC server

Conditional Ports (only if enabled)

CLI FlagDefaultProtocolDescription
--pprof.port6060TCPGo pprof profiling HTTP server (requires --pprof)
--metrics.port6061TCPPrometheus metrics HTTP server (requires --metrics)

Example: Two Instances

Instance 1 (using defaults):

./build/bin/erigon --datadir /path/to/datadir1

Instance 2 (all ports offset by +100):

./build/bin/erigon --datadir /path/to/datadir2 \
  --private.api.addr=127.0.0.1:9190 \
  --http.port=8645 \
  --authrpc.port=8651 \
  --ws.port=8646 \
  --torrent.port=42169 \
  --port=30403 \
  --caplin.discovery.port=4100 \
  --caplin.discovery.tcpport=4101 \
  --sentinel.port=7877 \
  --beacon.api.port=5655 \
  --mcp.port=8653

Notes

  • --private.api.addr takes a full host:port value, not just a port number.
  • The torrent port binds on both TCP and UDP; it is typically the first port conflict encountered at startup.
  • If --pprof or --metrics are enabled on both instances, their ports must also differ.