AWS Lightail Ubuntu 18.04服务器上的Docker mysql 5.7继续重启

Question

I have a script to install docker wordpress along with mysql server on ubuntu server. This script works perfectly OK on both ubuntu server 16.04 and 18.04 on VMWare on my local machine. This same script works on AwS lightsail ubuntu server 16.04 instance but not on 18.04. i don't get any error on script commands. entire process complete sucessfully but when i check runnign containers i see mysql container is keep rerstarting. This only happens on AWS lightsail ubuntu 18.04 instance. Can't figure out why. can anybody help please. script is as follows:

#!/bin/bash
apt-get -y update
apt-get -y install apt-transport-https ca-certificates curl software- 
properties-common
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -
apt-key fingerprint 0EBFCD88
add-apt-repository "deb [arch=amd64] 
https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable"
apt-get -y update
apt-get -y install docker-ce docker-compose

mkdir wordpress
cd wordpress

echo "file_uploads = On
memory_limit = 500M
upload_max_filesize = 500M
post_max_size = 500M
max_execution_time = 600" >> uploads.ini

echo "version: '3.3'

services:
   db:
     image: mysql:5.7
     volumes:
       - db_data:/var/lib/mysql
     restart: always
     environment:
       MYSQL_ROOT_PASSWORD: user
       MYSQL_DATABASE: wordpress
       MYSQL_USER: wordpress
       MYSQL_PASSWORD: user123

   wordpress:
     depends_on:
       - db
     image: wordpress:latest
     ports:
       - "80:80"
     restart: always
     environment:
       WORDPRESS_DB_HOST: db:3306
       WORDPRESS_DB_USER: wordpress
       WORDPRESS_DB_PASSWORD: user123
     volumes:
       - ./uploads.ini:/usr/local/etc/php/conf.d/uploads.ini
volumes:
    db_data: {}" >> docker-compose.yml

docker-compose up -d --build

Answer 1

I found issue with WORDPRESS_DB_HOST: db:3306 in db environment. i bring my yml script down to basic minimum and it worked. I also think mysql has issues with AWS lightsail ubuntu 18.04 server. Mariadb works perfectly OK. My final docker-compose.yml script on AWS lightsail ubuntu server 18.04 is:

wordpress:
  image: wordpress
  links:
    - wordpress_db:mysql
  ports:
    - 80:80
  volumes:
    - ./uploads.ini:/usr/local/etc/php/conf.d/uploads.ini
wordpress_db:
  image: mariadb
  environment:
    MYSQL_ROOT_PASSWORD: user123