dokku template refusing to serve apps to the browser

dokku-vm

Issue Details

After deploying the template, and following instructions in sedouard's README (which is the same template as yours but your doesn't include these instructions) I'm not able to access any of the apps, I'm seeing the following screen:

Repro steps

1. From https://github.com/Azure/azure-quickstart-templates/tree/master/dokku-vm, click on "Deploy to Azure" button, fill in the prompts after deploy finishes (resource group and a subdomain).
2. Open the IP address (or subdomain url) of the VM to be greeted with initial configuration window like this:
   
3. Fill in the above details using xip.io per instructions (I also tried our personal domain (rakapi.com) and the result was the same). Submit the form, after which the page can no longer be accessed.
4. I then run the following in the terminal to deploy my first app:

▶ cat ~/.ssh/id_rsa.pub | ssh atsepkov@104.40.55.9.xip.io "sudo sshcommand acl-add dokku atsepkov"
The authenticity of host '104.40.55.9.xip.io (104.40.55.9)' can't be established.
RSA key fingerprint is b1:01:e7:39:1e:41:32:4d:f2:c6:87:4e:39:b1:80:36.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '104.40.55.9.xip.io,104.40.55.9' (RSA) to the list of known hosts.
30:42:18:6f:b7:b4:2e:fb:f7:b7:58:4a:06:da:6d:fe
▶ git remote add xip dokku@104.40.55.9.xip.io:repo
▶ git push xip master
Counting objects: 39706, done.
Delta compression using up to 8 threads.
Compressing objects: 100% (12340/12340), done.

...

Successfully built 1f04d00412fd
-----> Releasing repo (dokku/repo:latest)...
-----> Deploying repo (dokku/repo:latest)...
-----> Attempting to run scripts.dokku.predeploy from app.json (if defined)
-----> No Procfile found in app image
-----> DOKKU_SCALE file not found in app image. Generating one based on Procfile...
-----> New DOKKU_SCALE file generated
=====> web=1
-----> Attempting pre-flight checks
       For more efficient zero downtime deployments, create a file CHECKS.
       See http://dokku.viewdocs.io/dokku/deployment/zero-downtime-deploys/ for examples
       CHECKS file not found in container: Running simple container check...
-----> Waiting for 10 seconds ...
-----> Default container check successful!
-----> Running post-deploy
-----> Attempting to run scripts.dokku.postdeploy from app.json (if defined)
=====> renaming container (6ce739f22ba0) hungry_noether to repo.web.1
-----> Creating new /home/dokku/repo/VHOST...
-----> Setting config vars
       DOKKU_PROXY_PORT_MAP: http:22:22
-----> Configuring repo.104.40.55.9.xip.io...(using built-in template)
-----> Creating http nginx.conf
-----> Running nginx-pre-reload
       Reloading nginx
-----> Setting config vars
       DOKKU_APP_RESTORE: 1
=====> Application deployed:
       http://repo.104.40.55.9.xip.io
       http://repo.104.40.55.9.xip.io:22

To dokku@104.40.55.9.xip.io:repo
 * [new branch]      master -> master

1. Now I navigate to http://repo.104.40.55.9.xip.io and am greeted with the same "Site can't be reached" screen I showed above.

I've tried to see if nginx is running and what version of dokku is deployed:

atsepkov@DokkuVM:~$ dokku version
0.7.1

atsepkov@DokkuVM:~$ ps aux | grep nginx
root     43495  0.0  0.1 121228  5640 ?        Ss   06:15   0:00 nginx: master process /usr/sbin/nginx -g daemon on; master_process on;
www-data 43496  0.0  0.0 121548  2624 ?        S    06:15   0:01 nginx: worker process
www-data 43497  0.0  0.0 121548  2624 ?        S    06:15   0:00 nginx: worker process
atsepkov 63802  0.0  0.0  10468  2128 pts/2    S+   13:30   0:00 grep --color=auto nginx

Start with the dokku-vm template and the linked dokku-azure README, then reproduce the Deploy to Azure flow using the listed xip.io steps. Check the reported Dokku 0.7.1 and nginx state while following the app deployment output; done means the deployed app and its subdomain load in a browser instead of showing the unreachable screen.