502 Bad Gateway

我正在使用nginx-proxy将子域连接到不同的docker服务.由于最后一次图像更新,我无法再连接到我的gitlab实例.我不知道nginx-proxy或gitlab更新是否导致了这个问题.当我尝试连接到gitlab.mydomain.com时,我收到以下错误：

>浏览器：502 Bad Gateway. nginx的/ 1.13.3
> nginx-proxy日志：

nginx-proxy_1 | nginx.1 | 2017/08/14 11:44:10 [错误] 39#39：* 1672 connect()失败(111：连接被拒绝)连接上游,客户端：178.201.120.94,服务器：gitlab.mydomain.com,请求： “GET / HTTP / 2.0”,上游：“https://172.18.0.2:443/”,主持人：“gitlab.mydomain.com”

nginx-proxy_1 | nginx.1 | gitlab.mydomain.com 178.201.120.94 – – [14 / Aug / 2017：11：44：10 0000]“GET / HTTP / 2.0”502 575“ – ”“Mozilla / 5.0(Windows NT 10.0; Win64; x64)AppleWebKit /537.36(KHTML,与Gecko一样)Chrome / 60.0.3112.90 Safari / 537.36“

nginx-proxy_1 | nginx.1 | 2017/08/14 11:44:11 [错误] 39#39：* 1672 connect()失败(111：连接被拒绝)连接上游,请求： “GET /favicon.ico HTTP / 2.0”,上游：“https://172.18.0.2:443/favicon.ico”,主持人：“gitlab.mydomain.com”,推荐人：“https://gitlab.***.com /”

我的docker-compose文件：

version: '2'

services:
   nginx-proxy:
     image: jwilder/nginx-proxy
     ports:
     - "80:80"
     - "443:443"
     volumes:
     - /var/local/nginx/certs:/etc/nginx/certs
     - /etc/letsencrypt:/etc/letsencrypt
     - /var/run/docker.sock:/tmp/docker.sock:ro

   gitlab:
     image: gitlab/gitlab-ce:latest
     ports:
     - "2222:22"
     hostname: 'gitlab.***.com'
     expose:
     - 443
     - 22
     - 80
     - 25
     environment:
     - "VIRTUAL_HOST=gitlab.***.com,www.gitlab.***.com"
     - "VIRTUAL_PORT=443"
     - "VIRTUAL_PROTO=https"
     volumes:
     - "gitlab-config:/etc/gitlab"
     - "gitlab-log:/var/log/gitlab"
     - "gitlab-data:/var/opt/gitlab"
     - "/etc/letsencrypt:/etc/letsencrypt"

有什么想法吗？谢谢.
编辑：
来自docker的网络设置检查gitlab：

    "NetworkSettings": {
        "Bridge": "","SandboxID": "...","HairpinMode": false,"LinkLocalIPv6Address": "","LinkLocalIPv6PrefixLen": 0,"Ports": {
            "22/tcp": [
                {
                    "HostIp": "0.0.0.0","HostPort": "2222"
                }
            ],"25/tcp": null,"443/tcp": null,"80/tcp": null
        },"SandboxKey": "/var/run/docker/netns/...","SecondaryIPAddresses": null,"SecondaryIPv6Addresses": null,"EndpointID": "","Gateway": "","GlobalIPv6Address": "","GlobalIPv6PrefixLen": 0,"IPAddress": "","IPPrefixLen": 0,"IPv6Gateway": "","MacAddress": "","Networks": {
            "docker_default": {
                "IPAMConfig": null,"Links": null,"Aliases": [
                    "abb170528bcc","gitlab"
                ],"NetworkID": "...","EndpointID": "...","Gateway": "172.18.0.1","IPAddress": "172.18.0.2","IPPrefixLen": 16,"MacAddress": "02:42:ac:12:00:02"
            }
        }
    }