lotus/documentation/en/setting-a-static-port.md

Static Ports

For a storage deal, you can set a static port for the Lotus Storage Miner.

Setup

To change the random swarm port, you may edit the config.toml file located under $LOTUS_STORAGE_PATH. The default location of this file is $HOME/.lotusstorage.

To change the port to 1347:

[Libp2p]
  ListenAddresses = ["/ip4/0.0.0.0/tcp/1347", "/ip6/::/tcp/1347"]

After changing the port value, restart your daemon.

Ubuntu's Uncomplicated Firewall

Open firewall manually:

ufw allow 1347/tcp

Or open and modify the profile located at /etc/ufw/applications.d/lotus-daemon:

[Lotus Daemon]
title=Lotus Daemon
description=Lotus Daemon firewall rules
ports=1347/tcp

Then run these commands:

ufw update lotus-daemon
ufw allow lotus-daemon