This video shows how to configure OpenBSD as a software based ethernet switch. That can operate at layer 2 and layer 3 or both. As well as how to combine this configuration with ip routing and firewalling using pf.
Resources:
https://www.openbsd.org
https://man.openbsd.org/bridge
https://man.openbsd.org/vether
Happy 3 year anniversary to all my viewers. Thank you so much for all of your support it means so much to me!