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I actually use both techniques together.

UFW

UFW is a great simple firewall, but at this point I do not recommend installing on your host. First, port forwarding is overly complex and seems like a hack versus it being very simple with IP Tables. 

If you insist on using UFW, make sure to change the setting to not drop forwarded packets. I will revisit this later as I do like UFW. Perhaps I can ask the developers to make port forwarding more straight-forward.

Installing UFW inside of a container is fine and has no issues.

Port Forwarding using IP Tables

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