title: 502 Bad Gateway for gitlab after a yum update
body: <p>I had a gitlab environnement that was working fine on CentOS 6, using port 8081 (apache already uses 80), and a yum update passed and now, I can't access my gitlab : 502 Bad Gateway
  The issue is... I don't understand much of what I'm doing. Configurating gitlab at first was not easy... But this time, I don't know what to do.</p>
  
  <p>In nginx logs (nginx has been installed from gitlab), I have : </p>
  
  <pre><code>2016/01/28 18:37:37 [crit] 31765#0: *1 connect() to unix:localhost:8081 failed (2: No such file or directory) while connecting to upstream, client: 59.118.47.19, server: gitlab.mydomain.com, request: "GET / HTTP/1.1", upstream: "http://unix:localhost:8081:/", host: "gitlab.mydomain.com:8081"
  </code></pre>
  
  <p>I already tried to check the conf, to use gitlab-ctl reconfigure, restart, but this doesn't seem to be changing anything at all.</p>
  
  <p>Here is the result from gitlab-ctl show-config</p>
  
  <pre><code>gitlab-ctl show-config
  [2016-01-28T18:42:27+01:00] WARN: Ohai::Config[:disabled_plugins] is set. Ohai::Config[:disabled_plugins] is deprecated and will be removed in future releases of ohai. Use ohai.disabled_plugins in your configuration file to configure :disabled_plugins for ohai.
  Starting Chef Client, version 12.5.1
  resolving cookbooks for run list: ["gitlab::show_config"]
  Synchronizing Cookbooks:
    - package (0.0.0)
    - runit (0.14.2)
    - gitlab (0.0.1)
  Compiling Cookbooks...
  {
    "gitlab": {
      "bootstrap": {
  
      },
      "omnibus-gitconfig": {
  
      },
      "manage-accounts": {
  
      },
      "user": {
        "git_user_email": "gitlab@gitlab.mydomain.com"
      },
      "redis": {
  
      },
      "ci-redis": {
  
      },
      "gitlab-rails": {
        "secret_token": "2e6c9197f8a81829348e8a29d0608976189abe04b0e28384428c49abcb8c8c9a5b95cfeac5b5f3e59",
        "gitlab_host": "gitlab.mydomain.com",
        "gitlab_email_from": "gitlab@gitlab.mydomain.com",
        "gitlab_https": false,
        "gitlab_port": 8081,
        "shared_path": "/var/opt/gitlab/gitlab-rails/shared",
        "artifacts_path": "/var/opt/gitlab/gitlab-rails/shared/artifacts",
        "lfs_storage_path": "/var/opt/gitlab/gitlab-rails/shared/lfs-objects",
        "pages_path": "/var/opt/gitlab/gitlab-rails/shared/pages",
        "db_username": "gitlab",
        "db_host": null,
        "db_port": 5432
      },
      "gitlab-ci": {
        "secret_token": null,
        "secret_key_base": "18f7e0e892c1cba94454a289abc285492afvd42909fbez364c9a4a45efc7c092b678e5b6bb986383",
        "db_key_base": "3fd05caaefd2ez3d5c5abc184fezi71962480936de4674609a6802b",
        "db_username": "gitlab_ci",
        "db_host": null,
        "db_port": 5432
      },
      "gitlab-shell": {
        "secret_token": "95f9af3zff567dcd70fbbc847dc67679d5e3717498294fhe97f978756f14bcca26f94b48db43f85008c1fab280d1e1ce3c21d4156369b"
      },
      "unicorn": {
  
      },
      "ci-unicorn": {
  
      },
      "sidekiq": {
  
      },
      "ci-sidekiq": {
  
      },
      "gitlab-workhorse": {
        "listen_addr": "localhost:8081",
        "auth_socket": "/var/opt/gitlab/gitlab-rails/sockets/gitlab.socket"
      },
      "mailroom": {
  
      },
      "nginx": {
        "listen_port": 8081
      },
      "ci-nginx": {
        "listen_port": 80
      },
      "mattermost-nginx": {
        "listen_port": null
      },
      "pages-nginx": {
        "listen_port": null
      },
      "logging": {
  
      },
      "remote-syslog": {
  
      },
      "logrotate": {
  
      },
      "high-availability": {
  
      },
      "postgresql": {
  
      },
      "web-server": {
  
      },
      "mattermost": {
        "email_invite_salt": "5723719e29c111gr11c34905c25e838da",
        "file_public_link_salt": "ede2ceb23d88reg83cc7060852525050251",
        "email_password_reset_salt": "9a79cff28e13fe248e53c3a13dc0d1f3aee",
        "sql_at_rest_encrypt_key": "f57d4bf0284dff8db5691ffc489b3f8312a1",
        "sql_data_source": "user=gitlab_mattermost host=/var/opt/gitlab/postgresql port=5432 dbname=mattermost_production",
        "sql_data_source_replicas": [
          "user=gitlab_mattermost host=/var/opt/gitlab/postgresql port=5432 dbname=mattermost_production"
        ]
      },
      "external-url": "http://gitlab.mydomain.com:8081",
      "ci-external-url": null,
      "mattermost-external-url": null,
      "pages-external-url": null
    }
  }
  Converging 0 resources
  
  Running handlers:
  Running handlers complete
  Chef Client finished, 0/0 resources updated in 01 seconds
  </code></pre>
  
  <p>If you have any pointers to what I could do/check, that would be great because I am kind of stucked (and as I don't understand much of what I'm doing... That doesn't help...)</p>
  
  <p>Thank you !</p>