mKCP + XTLS 通信错误，日志报 failed to read response version > EOF

[tsanie]

注：下列客户端配置把 xtls、xtlsSettings 修改为 tls、tlsSettings，移除 flow 后正常。

---

1. 你正在使用哪个版本的 V2Ray？（如果服务器和客户端使用了不同版本，请注明）
   服务端和客户端均为 4.31.0

2. 你的使用场景是什么？比如使用 Chrome 通过 Socks/VMess 代理观看 YouTube 视频。
   使用 Chrome 通过 VLESS 代理查看 google.com 首页

3. 你看到的不正常的现象是什么？（请描述具体现象，比如访问超时，TLS 证书错误等）
   意外终止连接：ERR_CONNECTION_CLOSED

4. 你期待看到的正确表现是怎样的？
   正确打开网页

5. 请附上你的配置（提交 Issue 前请隐藏服务器端IP地址）。

服务器端配置:

{
    "log": {
        "access": "",
        "error": "",
        "loglevel": "warning"
    },
    "inbounds": [
        {
            "port": 443,
            "protocol": "vless",
            "settings": {
                "clients": [
                    {
                        "id": "***",  // 留白
                        "level": 0,
                        "email": "me@vless.mkcp.tls",
                        "flow": "xtls-rprx-origin"
                    }
                ],
                "decryption": "none"
            },
            "streamSettings": {
                "network": "kcp",
                "security": "xtls",
                "xtlsSettings": {
                    "certificates": [
                        {
                            "certificateFile": "/path/to/fullchain.cer",  // 留白
                            "keyFile": "/path/to/private.key"  // 留白
                        }
                    ]
                },
                "kcpSettings": {
                    "mtu": 1200,
                    "tti": 20,
                    "uplinkCapacity": 12,
                    "downlinkCapacity": 100
                }
            }
        }
    ],
    "outbounds": [
        {
            "protocol": "freedom",
            "tag": "direct"
        },
        {
            "protocol": "blackhole",
            "tag": "blocked"
        }
    ],
    "routing": {
        "strategy": "rules",
        "settings": {
            "domainStrategy": "IPOnDemand",
            "rules": [
                {
                    "type": "field",
                    "protocol": [
                        "bittorrent"
                    ],
                    "outboundTag": "blocked"
                },
                {
                    "type": "field",
                    "ip": [
                        "geoip:private"
                    ],
                    "outboundTag": "blocked"
                }
            ]
        }
    }
}

客户端配置:

{
    "log": {
        "access": "",
        "error": "",
        "loglevel": "warning"
    },
    "inbounds": [
        {
            "port": 1111,
            "listen": "127.0.0.1",
            "protocol": "socks"
        }
    ],
    "outbounds": [
        {
            "protocol": "vless",
            "settings": {
                "vnext": [
                    {
                        "address": "***",  // 留白
                        "port": 443,
                        "users": [
                            {
                                "id": "***",  // 留白
                                "encryption": "none",
                                "flow": "xtls-rprx-origin"
                            }
                        ]
                    }
                ]
            },
            "streamSettings": {
                "network": "kcp",
                "security": "xtls",
                "xtlsSettings": {
                    "serverName": "***",  // 留白
                    "allowInsecure": false
                },
                "kcpSettings": {
                    "mtu": 1200,
                    "tti": 20,
                    "uplinkCapacity": 12,
                    "downlinkCapacity": 100
                }
            }
        },
        {
            "protocol": "freedom",
            "tag": "direct"
        },
        {
            "protocol": "blackhole",
            "tag": "blocked"
        }
    ],
    "routing": {
        "domainStrategy": "IPOnDemand",
        "rules": [
            {
                "type": "field",
                "ip": [
                    "geoip:private"
                ],
                "outboundTag": "blocked"
            },
            {
                "type": "field",
                "domain": [
                    "geosite:category-ads"
                ],
                "outboundTag": "blocked"
            }
        ]
    }
}

6. 请附上出错时软件输出的错误日志。在 Linux 中，日志通常在 /var/log/v2ray/error.log 文件中。

服务器端错误日志:

2020/10/10 22:13:00 [Warning] [400485014] v2ray.com/core/app/proxyman/inbound: connection ends > v2ray.com/core/proxy/vless/inbound: failed to use xtls-rprx-origin, maybe "security" is not "xtls"
2020/10/10 22:13:00 [Warning] [1747630384] v2ray.com/core/app/proxyman/inbound: connection ends > v2ray.com/core/proxy/vless/inbound: failed to use xtls-rprx-origin, maybe "security" is not "xtls"

// 注：见到这个错误提示我也第一时间检查了服务端和客户端的配置文件，确定 security 都是 xtls，配置项名也是 xtlsSettings

客户端错误日志:

2020/10/10 22:13:00 [Warning] [623766314] v2ray.com/core/app/proxyman/outbound: failed to process outbound traffic > v2ray.com/core/proxy/vless/outbound: connection ends > v2ray.com/core/proxy/vless/outbound: failed to decode response header > v2ray.com/core/proxy/vless/encoding: failed to read response version > EOF
2020/10/10 22:13:00 [Warning] [158083695] v2ray.com/core/app/proxyman/outbound: failed to process outbound traffic > v2ray.com/core/proxy/vless/outbound: connection ends > v2ray.com/core/proxy/vless/outbound: failed to decode response header > v2ray.com/core/proxy/vless/encoding: failed to read response version > EOF

7. 请附上访问日志。在 Linux 中，日志通常在 /var/log/v2ray/access.log 文件中。

    // 在这里附上服务器端日志

8. 其它相关的配置文件（如 Nginx）和相关日志。

9. 如果 V2Ray 无法启动，请附上 --test 输出。

10. 如果 V2Ray 服务运行不正常，请附上 journal 日志。

[RPRX]

普遍问题，请等待修复

[RPRX]

ff6bb51 大概半个小时后编译机器人会在该链接下方评论，请测试一下

[tsanie]

ff6bb51 大概半个小时后编译机器人会在该链接下方评论，请测试一下

经测试可以了，打开环境变量 V2RAY_VLESS_XTLS_SHOW = true 后服务端和客户端分别出现大量 XTLS sent XTLS received 日志，已生效。

[RPRX]

ff6bb51 大概半个小时后编译机器人会在该链接下方评论，请测试一下

经测试可以了，打开环境变量 V2RAY_VLESS_XTLS_SHOW = true 后服务端和客户端分别出现大量 XTLS sent XTLS received 日志，已生效。

感谢测试与反馈