github.com/mholt/caddy-l4@v0.0.0-20241104153248-ec8fae209322/integration/caddyfile_adapt/gd_handler_tee.caddytest

{
	layer4 {
		0.0.0.0:443 {
			@external not remote_ip 192.168.0.0/16
			route @external {
				tee {
					proxy primary.machine.local:443
					proxy secondary.machine.local:443
				}
			}
			route {
				echo
			}
		}
	}
}
----------
{
	"apps": {
		"layer4": {
			"servers": {
				"srv0": {
					"listen": [
						"0.0.0.0:443"
					],
					"routes": [
						{
							"match": [
								{
									"not": [
										{
											"remote_ip": {
												"ranges": [
													"192.168.0.0/16"
												]
											}
										}
									]
								}
							],
							"handle": [
								{
									"branch": [
										{
											"handler": "proxy",
											"upstreams": [
												{
													"dial": [
														"primary.machine.local:443"
													]
												}
											]
										},
										{
											"handler": "proxy",
											"upstreams": [
												{
													"dial": [
														"secondary.machine.local:443"
													]
												}
											]
										}
									],
									"handler": "tee"
								}
							]
						},
						{
							"handle": [
								{
									"handler": "echo"
								}
							]
						}
					]
				}
			}
		}
	}
}