Nginx – Docker: Can’t find the host in the upstream application: 9000

server {
 listen 80;
 listen 443 ssl http2;

 # Server name being used (exact name, wildcards or regular expression)
 server_name localhost;
 client_max_body_size 200M;

 # Document root, make sure this points to your Phalcon web directory
 root /var/www/html /public;
 index index.php index.html;

 location / {
 try_files $uri $uri/ /index.php?_url=$uri&$args;
 }

 location ~ \.php${
 fastcgi_pass app:9000;
 # regex to split $uri to $fastcgi_script_name and $fastcgi_path
 fastcgi_split_path_info ^( .+\.php)(/.+)$;
 fastcgi_index index. php;

 include fastcgi_params;

 # Bypass the fact that try_files resets $fastcgi_path_info
 # see: http://trac.nginx.org/nginx/ticket /321
 set $path_info $fastcgi_path_info;
 fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
 fastcgi_param APPLICATION_ENV development;

 #add_header Authorization $http_authorization;
} 

 # Logging
 error_log /var/log/nginx/error.log;
 access_log /var/log/nginx/access.log;
}

db:
 image: mysql:latest
 container_name: dev_db
 expose:
-"3306"
 ports:
-"3307:3306"
 environment:
 MYSQL_DATABASE: dbname
 MYSQL_USER: person
 MYSQL_PASSWORD: secret
 MYSQL_ROOT_PASSWORD: secret
app:
 image: linxlad/php7-fpm
 container_name: dev_app
 tty: true
 ports :
-"6900:6900"
 volumes:
-./logs/php-fpm:/var/log/php-fpm
-..:/var/www /html
 links:
-db
web:
 tty: true
 image: linxlad/nginx
 container_name: dev_web
 ports:< br />-"8080:80"
 volumes:
-./conf/nginx:/etc/nginx/conf.d
-./logs/nginx:/var/log/ nginx
-..:/var/www/html
 links:
-app

web:
 tty: true
 image: linxlad/nginx
 container_name: dev_web
 ports:
- "8080:80"
 volumes:
-./conf/nginx:/etc/nginx/conf.d
-./logs/nginx:/var/log/nginx
-..:/var/www/html
 links:
-app
 depends_on:
-app

This composer file used to work until a week ago (no change). I ran it again at home by adding dns:8.8.8.8 to the docker-compose.yml file.

This made me believe This problem is related to DNS.

Now I try to run it on a different machine (at work) but the following error occurs:
nginx: [emerg] host is in /etc/nginx/sites-enabled “app:9000” upstream on /default.conf:2 cannot be found

I am not sure what this means. This is my nginx conf:

server {
 listen 80;
 listen 443 ssl http2;

 # Server name being used (exact name, wildcards or regular expression)
 server_na me localhost;
 client_max_body_size 200M;

 # Document root, make sure this points to your Phalcon web directory
 root /var/www/html/public;
 index index.php index.html;

 location / {
 try_files $uri $uri/ /index.php?_url=$uri&$args;
 }
< br /> location ~ \.php${
 fastcgi_pass app:9000;
 # regex to split $uri to $fastcgi_script_name and $fastcgi_path
 fastcgi_split_path_info ^(.+\.php)(/ .+)$;
 fastcgi_index index.php;

 include fastcgi_params;

 # Bypass the fact that try_files resets $fastcgi_path_info
 # see: http ://trac.nginx.org/nginx/ticket/321
 set $path_info $fastcgi_path_info;
 fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
 fastcgi_param APPLICATION_ENV development;

 #add_header Authorization $http_authorization;
 }

 # Loggi ng
 error_log /var/log/nginx/error.log;
 access_log /var/log/nginx/access.log;
}

And my docker -compose.yml file:

db:
 image: mysql:latest
 container_name: dev_db
 expose:
-" 3306"
 ports:
-"3307:3306"
 environment:
 MYSQL_DATABASE: dbname
 MYSQL_USER: person
 MYSQL_PASSWORD: secret
 MYSQL_ROOT_PASSWORD : secret
app:
 image: linxlad/php7-fpm
 container_name: dev_app
 tty: true
 ports:
-"6900:6900"< br /> volumes:
-./logs/php-fpm:/var/log/php-fpm
-..:/var/www/html
 links:
 -db
web:
 tty: true
 image: linxlad/nginx
 container_name: dev_web
 ports:
-"8080:80"
 volumes:
-./conf/nginx:/etc/nginx/conf.d
-./logs/nginx:/var/log/nginx
-..:/var/ www/html
 links:
-app

The repo is here.

Does anyone know how to correct this problem?

Thank you

Your nginx container may be started before your application. You should add one in the docker-compose.yml file The depends_on part tells docker the order in which the containers should be started

https://docs.docker.com/compose/compose-file/#depends_on

< pre>web:
tty: true
image: linxlad/nginx
container_name: dev_web
ports:
-“8080:80”
volumes:< br />-./conf/nginx:/etc/nginx/conf.d
-./logs/nginx:/var/log/nginx
-..:/var/www/html< br /> links:
-app
depends_on:
-app