openwrt-xray/etc/xray/config/dns.jsonc

{
    "dns": {
        "tag": "dns-in",
        "hosts": {
            "dns.google": "8.8.8.8"
        },
        "servers": [
            "https://dns.google/dns-query",
            {
                "address": "localhost",
                "disableFallback": true,
                "domains": [
                    "regexp:.*\\.lan"
                ]
            }
        ],
        "queryStrategy": "UseIPv4"
    }
}