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

Static Ports

Depending on how your network is set up, you may need to set a static port to successfully connect to peers to perform storage deals with your 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