Why can't connect to postgres server in docker container?

Question

CentOS

1. Have a Windows 10 Host on it --> Virtual Box on it ---> (Vagrant + CentOS 8).
2. The network between Windows 10 and CentOS works through nat
3. Docker with containers is up on CentOS

Containers

Containers lifted through docker-compose

Here is the config

version: "3.8"
services:

  db:
    image: postgres:12.3-alpine
    container_name: postgres
    ports:
      - "5432:5432"
    volumes:
      - "./pg_data:/var/lib/postgresql/data/pg_data"
    environment:
      POSTGRES_PASSWORD: 123
      POSTGRES_DB: movieblog
      PGDATA: /var/lib/postgresql/data/pg_data
    restart: always

  adminer:
    image: adminer
    ports:
      - "8080:8080"
    restart: always

4. On the virtual box, I forwarded the ports from the host to the guest

Ports

5. Gave port 5432 Accept in INPUT iptables

iptables

added port to firewall-cmd

firewall

As a result, I get to the admin panel (adminer) through port 8080, I enter data but I can’t log in

Main problem

How to be??

Answer 1

CentOS 8 switched to a new firewall subsystem - nftables, and Docker only supports iptables, then networking inside containers will not work. To fix this, enable masquerade traffic with firewalld:

firewall-cmd --zone=public --add-masquerade --permanent

Then restart the firewall so that the active rules are updated:
firewall-cmd --reload

Answer 2

why are you specifying the postgres database in adminir-e when the database is called movieblog in docker-compose ?

Answer 3

soldering iron)

Answer 4

Some players have this option (foobar, vl, mpc), or a hard version:
3.5mm stereo to 2 RCA male plugs + 3.5mm stereo to 2 RCA female - change white tulips to red - profit
Or a very harsh option - if you have a soldering iron, well, you understand)
About the soldering iron I’m already filming the version ... ahead of