erigon-network-ports

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 Flag	Default	Protocol	Description
--private.api.addr	127.0.0.1:9090	TCP (gRPC)	Internal gRPC API for component communication (txpool, rpcdaemon, sentry, downloader)
--http.port	8545	TCP	JSON-RPC HTTP server
--authrpc.port	8551	TCP	Engine API (consensus layer auth RPC)
--ws.port	8546	TCP	WebSocket RPC server
--torrent.port	42069	TCP+UDP	BitTorrent protocol for snapshot downloads
--port	30303	TCP+UDP	DevP2P network listening port
--p2p.allowed-ports	30303,30304,30305,30306,30307	TCP+UDP	Additional ports for different eth p2p protocol versions
--caplin.discovery.port	4000	UDP	Caplin consensus DISCV5 discovery
--caplin.discovery.tcpport	4001	TCP	Caplin consensus DISCV5 TCP
--sentinel.port	7777	TCP	Sentinel (consensus p2p service)
--beacon.api.port	5555	TCP	Beacon Chain REST API
--mcp.port	8553	TCP	MCP (Model Context Protocol) RPC server

Conditional Ports (only if enabled)

CLI Flag	Default	Protocol	Description
--pprof.port	6060	TCP	Go pprof profiling HTTP server (requires --pprof)
--metrics.port	6061	TCP	Prometheus 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 \
  --p2p.allowed-ports=30403,30404,30405,30406,30407 \
  --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.
• --p2p.allowed-ports must list 5 consecutive ports matching the base --port value (one per eth p2p protocol version).
• 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.