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The bulk of the configuration is established by setting properties in "ini" files that are combined in the start.d directory. Some of the properties are defined by Jetty and configure built-in modules and others are specific to the IdP and configure the custom modules we created.
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Use the setuid extension to support listening on the privileged ports as a non-root user.
Use a port forwarding approach (load balancer, iptables rules, etc).
Adjust the range of ports considered privileged if supported by your Linux kernel.
Use POSIX capabilities to allow use of priviledged ports by an unpriviledged process, e.g. when using systemd by setting
AmbientCapabilities=CAP_NET_BIND_SERVICE
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Jetty documents a way to adjust this sort of thing here. The basic procedure is to create a file at etc/tls-config.xml to adjust the settings. You should do some testing against SSL Labs or some other source of information to evaluate what the defaults look like and make any adjustments you think are warranted.
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