群晖NAS安装卸载Traefik后MariaDB容器超时无法访问求助

之前在群晖NAS上运行MariaDB容器完全正常，安装Traefik后因无关问题卸载，之后所有内部容器都无法访问数据库：

• 通过Adminer或PHPMyAdmin容器连接时出现超时错误
• 电脑上通过指向NAS的域名用HeidiSQL却能正常连接
• OwnCloud部署受影响，owncloud/server容器抛出**"Database didn't come up in time!"**错误

查看MariaDB容器日志未发现任何错误或警告，已尝试以下操作但问题仍未解决：

• 重装所有容器镜像及群晖Container Manager
• 修改各类配置项、反向代理设置与防火墙设置

相关配置文件 #

docker-compose.yml #

version: "3.1"

services:
    phpmyadmin:
        image: phpmyadmin:latest
        restart: unless-stopped
        ports:
            - 8080:80
        volumes:
            - /volume1/docker/mariadb/phpmyadmin.php:/etc/phpmyadmin/config.user.inc.php
        networks:
            - pma
        depends_on:
            - instance-1

    instance-1:
        image: mariadb:latest
        restart: unless-stopped
        container_name: mariadb-instance-1
        env_file: /volume1/docker/mariadb/instance-1/mariadb.env
        ports:
            - "8081:3306"
        volumes:
            - /volume1/docker/mariadb/instance-1/data:/var/lib/mysql
            - /volume1/docker/mariadb/instance-1/my.cnf:/etc/mysql/my.cnf
        networks:
            - pma
            - mariadb_network

networks:
    pma:
    mariadb_network:

my.cnf #

[client-server]
# Port or socket location where to connect
port = 3306
socket = /run/mysqld/mysqld.sock

# !includedir /etc/mysql/mariadb.conf.d/
# !includedir /etc/mysql/conf.d/

[mysqld]
bind-address=0.0.0.0
character-set-server = utf8mb4
collation-server = utf8mb4_unicode_ci
query-cache-type = ON
innodb-buffer-pool-size = 512M

[client]
default-character-set = utf8mb4

mariadb.env #

TZ=UTC
MARIADB_ROOT_PASSWORD=...
MARIADB_USER=...
MARIADB_PASSWORD=...

phpmyadmin.php #

<?php

$cfg['DefaultConnectionCollation'] = "utf8mb4_unicode_ci";
$cfg['FirstDayOfCalendar'] = 1;
$cfg["Console"]["Mode"] = "collapse";

$cfg['Servers'][1]['host'] = "mariadb-instance-1";
$cfg['Servers'][1]['port'] = "3306";
$cfg['Servers'][1]['auth_type'] = "cookie";

内容的提问来源于stack exchange，提问作者James