What ports does P2Pool use?

P2Pool normally uses port 3333 for your miners, plus 37889 for the main P2Pool network or 37888 for P2Pool mini. It also connects to your Monero node, usually through 18081 for RPC and 18083 for ZMQ—but you should not open all these ports to the internet.

Ports for miners and P2Pool peers

A port is a numbered connection point on your computer. Different services use different ports so traffic reaches the right place.

These are the usual P2Pool defaults:

• 3333 — Stratum: Your mining software connects here to receive work and submit results. Stratum is the communication method used between your miner and P2Pool.
• 37889 — Main P2Pool peer connections: Your P2Pool instance uses this to communicate with other computers on the main P2Pool network.
• 37888 — P2Pool mini peer connections: This serves the same purpose when you run P2Pool with the --mini option.

You use the peer port for the P2Pool network you actually run. You do not need both main and mini ports open for one instance.

These defaults can be changed. If you followed a custom setup guide, check your startup options rather than assuming the default numbers apply.

Ports for your Monero node

P2Pool needs access to a Monero node, the software that checks Monero transactions and blocks. That introduces a separate set of connections:

• 18081 — RPC: Remote Procedure Call is the interface P2Pool uses to ask your node for information and submit blocks.
• 18083 — ZMQ: ZeroMQ is a messaging system that lets your node quickly notify P2Pool about new activity. This is the usual port configured for P2Pool; you must enable the node’s ZMQ publisher.
• 18080 — Monero peer connections: Your node uses this to communicate with other Monero nodes. It is not a miner connection port.

For a typical local setup, the node options include --zmq-pub tcp://127.0.0.1:18083. The address 127.0.0.1, called localhost, means “this computer.”

What to allow through your firewall

These connections use TCP, a standard way computers send data over a network.

For a typical home setup:

• Allow outbound connections so your node and P2Pool can find peers.
• Optionally allow inbound 37889 or 37888, matching your P2Pool network. This helps other P2Pool peers reach you.
• Optionally allow inbound 18080 to help other Monero nodes connect to yours.
• Allow 3333 only from the computers you want mining through your instance.

Router port forwarding is generally not required to start mining. It lets unsolicited connections from the internet reach a service inside your home network.

Keep RPC 18081 and ZMQ 18083 private. If your node runs on another computer, use a trusted private network or a securely configured connection rather than exposing these interfaces publicly.

The bottom line

Remember 3333 for miners, 37889 for main P2Pool, and 37888 for mini. P2Pool also needs your node’s RPC and ZMQ connections, usually 18081 and 18083. Open only what your setup needs, and keep node control interfaces off the public internet.