caddy/caddytest/integration/caddyfile_adapt/tls_acme_preferred_chains.txt

localhost

tls {
	issuer acme {
		preferred_chains {
			any_common_name "Generic CA 1" "Generic CA 2"
		}
	}
}
----------
{
	"apps": {
		"http": {
			"servers": {
				"srv0": {
					"listen": [
						":443"
					],
					"routes": [
						{
							"match": [
								{
									"host": [
										"localhost"
									]
								}
							],
							"terminal": true
						}
					]
				}
			}
		},
		"tls": {
			"automation": {
				"policies": [
					{
						"subjects": [
							"localhost"
						],
						"issuers": [
							{
								"module": "acme",
								"preferred_chains": {
									"any_common_name": [
										"Generic CA 1",
										"Generic CA 2"
									]
								}
							}
						]
					}
				]
			}
		}
	}
}