Puma not creating socket at defined location when started with `rails server` - ruby-on-rails

Question

I'm deploying my Rails app using nginx, puma, and capistrano. It's deployed by a user called deploy and the deploy location is under the home directory (/home/deploy)
I have Puma configured to create a socket under the shared folder that Capistrano symlinks all it's releases to. Correspondingly, nginx is configured to look at that socket as well (see config files below)
However when I start up the Rails / Puma webserver -
cd /home/deploy/my_app/current
SECRET_KEY_BASE=.... DATABASE_PASSWORD=... rails s -e production
I notice that no socket file is created. When I visit the site in my browser and then look at the Nginx error log, it is also complaining about that socket not existing.
2016/07/17 14:26:19 [crit] 26055#26055: *12 connect() to unix:/home/deploy/my_app/shared/tmp/sockets/puma.sock failed (2: No such file or directory) while connecting to upstream, client: XX.YY.XX.YY, server: localhost, request: "GET http://testp4.pospr.waw.pl/testproxy.php HTTP/1.1", upstream: "http://unix:/home/deploy/my_app/shared/tmp/sockets/puma.sock:/500.html", host: "testp4.pospr.waw.pl"
How do I go about getting puma to create that socket?
Thanks!
Puma Config
# config/puma.rb
...
# `shared_dir` is the symlinked `shared/` directory created
# by Capistrano - `/home/deploy/my_app/shared`
# Set up socket location
bind "unix://#{shared_dir}/tmp/sockets/puma.sock"
# Logging
stdout_redirect "#{shared_dir}/log/puma.stdout.log", "#{shared_dir}/log/puma.stderr.log", true
# Set master PID and state locations
pidfile "#{shared_dir}/tmp/pids/puma.pid"
state_path "#{shared_dir}/tmp/pids/puma.state"
activate_control_app
...
Nginx sites config
# /etc/nginx/sites-available/default
upstream app {
# Path to Puma SOCK file
server unix:/home/deploy/my_app/shared/tmp/sockets/puma.sock fail_timeout=0;
}
server {
listen 80;
server_name localhost;
root /home/deploy/my_app/public;
try_files $uri/index.html $uri #app;
location #app {
proxy_pass http://app;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header Host $http_host;
proxy_redirect off;
}
error_page 500 502 503 504 /500.html;
client_max_body_size 4G;
keepalive_timeout 10;
}

Answer 1

Are you sure you are running Puma with that configuration? I don't think rails server is the proper way to start Puma in a production environment.
I would use this instead:
RACK_ENV=production bundle exec puma -C config/puma.rb
Once you get this working manually, then use the --daemon flag to keep the server running in the background.
Also, where is shared_dir defined in your config/puma.rb? Perhaps you omitted the part of the file, but if not, make sure you insert the correct value.

Answer 2

I had a similar issue, the reason was in the incorrect value of shared_dir. You need to update with following if you want to work it on deploy:
set :puma_bind,-> { "unix://#{shared_path}/tmp/sockets/puma.sock" }
set :puma_state, -> { "#{shared_path}/tmp/pids/puma.state" }
set :puma_pid, -> { "#{shared_path}/tmp/pids/puma.pid" }
Notice: after this changes you may have a problem with manual runcap production puma:start/stop/restart and you will need to remove -> {.