The "best" way in my opinion is to use Apache as a proxy to your Glassfish instance(s). You then create and configure Apache virtual hosts that proxy to the required GF listener ports.
This solution is very flexible and does not require GF to listen to port 80 (which has other implications). As an example, we have 6 different GF instances (with up to 5 listeners per instance) being proxied by Apache virtual hosts. It works really well and even SSL is handled by Apache with no problems (and without the need to configure SSL in GF)
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