Unknown MySQL server host 'mysql'

CMS Version

4.0.6.

Installation Method

Docker

Operating System

Debian GNU/Linux 11 (bullseye)

Issue

can’t connect to mysql

docker-compose logs cms-web

cms-web_1         | Configuring Database Settings
cms-web_1         | ERROR 2005 (HY000): Unknown MySQL server host 'mysql' (-2)
cms-web_1         | ERROR 2005 (HY000): Unknown MySQL server host 'mysql' (-2)
cms-web_1         | ERROR 2005 (HY000): Unknown MySQL server host 'mysql' (-2)
cms-web_1         | ERROR 2005 (HY000): Unknown MySQL server host 'mysql' (-2)
cms-web_1         | ERROR 2005 (HY000): Unknown MySQL server host 'mysql' (-2)
cms-web_1         | ERROR 2005 (HY000): Unknown MySQL server host 'mysql' (-2)
cms-web_1         | Setting up Maintenance
cms-web_1         | Protected Maintenance
cms-web_1         | ERROR 2005 (HY000): Unknown MySQL server host 'mysql' (-2)
cms-web_1         | ERROR 2005 (HY000): Unknown MySQL server host 'mysql' (-2)
cms-web_1         | Importing ca-certs
cms-web_1         | cp: cannot stat '/var/www/cms/ca-certs/*.pem': No such file or directory
cms-web_1         | cp: cannot stat '/var/www/cms/ca-certs/*.crt': No such file or directory
cms-web_1         | Updating certificates in /etc/ssl/certs...
cms-web_1         | 0 added, 0 removed; done.
cms-web_1         | Running hooks in /etc/ca-certificates/update.d...
cms-web_1         | done.
cms-web_1         | Setting up Quickchart
cms-web_1         | ERROR 2005 (HY000): Unknown MySQL server host 'mysql' (-2)
cms-web_1         | ERROR 2005 (HY000): Unknown MySQL server host 'mysql' (-2)
cms-web_1         | Configuring Maintenance
cms-web_1         | Removing web/install/index.php from production container
cms-web_1         | ERROR 2005 (HY000): Unknown MySQL server host 'mysql' (-2)
cms-web_1         | Configure PHP
cms-web_1         | Configure Apache
cms-web_1         | Starting cron
cms-web_1         | Starting webserver
cms-web_1         | AH00558: apache2: Could not reliably determine the server's fully qualified domain name, using 172.24.0.6. Set the 'ServerName' directive globally to suppress this message

calling over Browser:

Fatal Error - sorry this shouldn’t happen.
SQLSTATE[HY000] [2002] php_network_getaddresses: getaddrinfo for mysql failed: Name or service not known

I had a running 2.3.x Xibo version and tried to update up to 3.3. but also got this error. Then I tried to go back and used the backup files, I got the same error like above. Then I removed everything. clean up all Docker Images, container and everything in the folder. Now I tried directly the last version 4.0.6 and I got this error.

The only change I do is using an Apache2 to serve https like describe here Xibo for Docker | Xibo Digital Signage

What can I do to find the solution?

EDIT:
May I show also the logs from the db

cms-db_1          | 2024-01-25 12:29:19+00:00 [Note] [Entrypoint]: Entrypoint script for MySQL Server 8.0.36-1.el8 started.
cms-db_1          | 2024-01-25 12:29:21+00:00 [Note] [Entrypoint]: Switching to dedicated user 'mysql'
cms-db_1          | 2024-01-25 12:29:21+00:00 [Note] [Entrypoint]: Entrypoint script for MySQL Server 8.0.36-1.el8 started.
cms-db_1          | 2024-01-25 12:29:21+00:00 [Note] [Entrypoint]: Initializing database files
cms-db_1          | 2024-01-25T12:29:21.513291Z 0 [Warning] [MY-011068] [Server] The syntax '--skip-host-cache' is deprecated and will be removed in a future release. Please use SET GLOBAL host_cache_size=0 instead.
cms-db_1          | 2024-01-25T12:29:21.515662Z 0 [System] [MY-013169] [Server] /usr/sbin/mysqld (mysqld 8.0.36) initializing of server in progress as process 81
cms-db_1          | 2024-01-25T12:29:21.589681Z 1 [System] [MY-013576] [InnoDB] InnoDB initialization has started.
cms-db_1          | 2024-01-25T12:29:25.482120Z 1 [System] [MY-013577] [InnoDB] InnoDB initialization has ended.
cms-db_1          | 2024-01-25T12:29:33.852258Z 6 [Warning] [MY-010453] [Server] root@localhost is created with an empty password ! Please consider switching off the --initialize-insecure option.
cms-db_1          | 2024-01-25 12:29:51+00:00 [Note] [Entrypoint]: Database files initialized
cms-db_1          | 2024-01-25 12:29:51+00:00 [Note] [Entrypoint]: Starting temporary server
cms-db_1          | 2024-01-25T12:29:52.209979Z 0 [Warning] [MY-011068] [Server] The syntax '--skip-host-cache' is deprecated and will be removed in a future release. Please use SET GLOBAL host_cache_size=0 instead.
cms-db_1          | 2024-01-25T12:29:52.211943Z 0 [System] [MY-010116] [Server] /usr/sbin/mysqld (mysqld 8.0.36) starting as process 123
cms-db_1          | 2024-01-25T12:29:52.253796Z 1 [System] [MY-013576] [InnoDB] InnoDB initialization has started.
cms-db_1          | 2024-01-25T12:29:53.418597Z 1 [System] [MY-013577] [InnoDB] InnoDB initialization has ended.
cms-db_1          | 2024-01-25T12:29:53.942185Z 0 [Warning] [MY-010068] [Server] CA certificate ca.pem is self signed.
cms-db_1          | 2024-01-25T12:29:53.942239Z 0 [System] [MY-013602] [Server] Channel mysql_main configured to support TLS. Encrypted connections are now supported for this channel.
cms-db_1          | 2024-01-25T12:29:53.953167Z 0 [Warning] [MY-011810] [Server] Insecure configuration for --pid-file: Location '/var/run/mysqld' in the path is accessible to all OS users. Consider choosing a different directory.
cms-db_1          | 2024-01-25T12:29:53.985428Z 0 [System] [MY-011323] [Server] X Plugin ready for connections. Socket: /var/run/mysqld/mysqlx.sock
cms-db_1          | 2024-01-25T12:29:53.985487Z 0 [System] [MY-010931] [Server] /usr/sbin/mysqld: ready for connections. Version: '8.0.36'  socket: '/var/run/mysqld/mysqld.sock'  port: 0  MySQL Community Server - GPL.
cms-db_1          | 2024-01-25 12:29:54+00:00 [Note] [Entrypoint]: Temporary server started.
cms-db_1          | '/var/lib/mysql/mysql.sock' -> '/var/run/mysqld/mysqld.sock'
cms-db_1          | Warning: Unable to load '/usr/share/zoneinfo/iso3166.tab' as time zone. Skipping it.
cms-db_1          | Warning: Unable to load '/usr/share/zoneinfo/leap-seconds.list' as time zone. Skipping it.
cms-db_1          | Warning: Unable to load '/usr/share/zoneinfo/leapseconds' as time zone. Skipping it.
cms-db_1          | Warning: Unable to load '/usr/share/zoneinfo/tzdata.zi' as time zone. Skipping it.
cms-db_1          | Warning: Unable to load '/usr/share/zoneinfo/zone.tab' as time zone. Skipping it.
cms-db_1          | Warning: Unable to load '/usr/share/zoneinfo/zone1970.tab' as time zone. Skipping it.
cms-db_1          | 2024-01-25 12:29:57+00:00 [Note] [Entrypoint]: GENERATED ROOT PASSWORD: 7rj27FJvMgP684f8ynkaM8bxXYk+9jSb
cms-db_1          | 2024-01-25 12:29:57+00:00 [Note] [Entrypoint]: Creating database cms
cms-db_1          | 2024-01-25 12:29:58+00:00 [Note] [Entrypoint]: Creating user cms
cms-db_1          | 2024-01-25 12:29:58+00:00 [Note] [Entrypoint]: Giving user cms access to schema cms
cms-db_1          | 
cms-db_1          | 2024-01-25 12:29:58+00:00 [Note] [Entrypoint]: Stopping temporary server
cms-db_1          | 2024-01-25T12:29:58.254524Z 13 [System] [MY-013172] [Server] Received SHUTDOWN from user root. Shutting down mysqld (Version: 8.0.36).
cms-db_1          | 2024-01-25T12:30:05.816145Z 0 [System] [MY-010910] [Server] /usr/sbin/mysqld: Shutdown complete (mysqld 8.0.36)  MySQL Community Server - GPL.
cms-db_1          | 2024-01-25 12:30:06+00:00 [Note] [Entrypoint]: Temporary server stopped
cms-db_1          | 
cms-db_1          | 2024-01-25 12:30:06+00:00 [Note] [Entrypoint]: MySQL init process done. Ready for start up.
cms-db_1          | 
cms-db_1          | 2024-01-25T12:30:06.536961Z 0 [Warning] [MY-011068] [Server] The syntax '--skip-host-cache' is deprecated and will be removed in a future release. Please use SET GLOBAL host_cache_size=0 instead.
cms-db_1          | 2024-01-25T12:30:06.538784Z 0 [System] [MY-010116] [Server] /usr/sbin/mysqld (mysqld 8.0.36) starting as process 1
cms-db_1          | 2024-01-25T12:30:06.546990Z 1 [System] [MY-013576] [InnoDB] InnoDB initialization has started.
cms-db_1          | 2024-01-25T12:30:07.130418Z 1 [System] [MY-013577] [InnoDB] InnoDB initialization has ended.
cms-db_1          | 2024-01-25T12:30:07.906440Z 0 [Warning] [MY-010068] [Server] CA certificate ca.pem is self signed.
cms-db_1          | 2024-01-25T12:30:07.906490Z 0 [System] [MY-013602] [Server] Channel mysql_main configured to support TLS. Encrypted connections are now supported for this channel.
cms-db_1          | 2024-01-25T12:30:07.941971Z 0 [Warning] [MY-011810] [Server] Insecure configuration for --pid-file: Location '/var/run/mysqld' in the path is accessible to all OS users. Consider choosing a different directory.
cms-db_1          | 2024-01-25T12:30:07.976332Z 0 [System] [MY-011323] [Server] X Plugin ready for connections. Bind-address: '::' port: 33060, socket: /var/run/mysqld/mysqlx.sock
cms-db_1          | 2024-01-25T12:30:07.976394Z 0 [System] [MY-010931] [Server] /usr/sbin/mysqld: ready for connections. Version: '8.0.36'  socket: '/var/run/mysqld/mysqld.sock'  port: 3306

Is there anybody who could help me to find the problem? May I miss some informations?

I always get this logs if I restart the Containers. The curios thing is, I got the same message with all versions I tried.

physik-info-02:/data/xibo # docker-compose logs 
Attaching to xibo_cms-web_1, xibo_cms-memcached_1, xibo_cms-xmr_1, xibo_cms-db_1, xibo_cms-quickchart_1
cms-db_1          | 2024-01-26 07:40:49+00:00 [Note] [Entrypoint]: Entrypoint script for MySQL Server 8.0.36-1.el8 started.
cms-db_1          | 2024-01-26 07:40:50+00:00 [Note] [Entrypoint]: Switching to dedicated user 'mysql'
cms-db_1          | 2024-01-26 07:40:50+00:00 [Note] [Entrypoint]: Entrypoint script for MySQL Server 8.0.36-1.el8 started.
cms-db_1          | '/var/lib/mysql/mysql.sock' -> '/var/run/mysqld/mysqld.sock'
cms-db_1          | 2024-01-26T07:40:51.190956Z 0 [Warning] [MY-011068] [Server] The syntax '--skip-host-cache' is deprecated and will be removed in a future release. Please use SET GLOBAL host_cache_size=0 instead.
cms-db_1          | 2024-01-26T07:40:51.192306Z 0 [System] [MY-010116] [Server] /usr/sbin/mysqld (mysqld 8.0.36) starting as process 1
cms-db_1          | 2024-01-26T07:40:51.212822Z 1 [System] [MY-013576] [InnoDB] InnoDB initialization has started.
cms-db_1          | 2024-01-26T07:40:52.621335Z 1 [System] [MY-013577] [InnoDB] InnoDB initialization has ended.
cms-db_1          | 2024-01-26T07:40:53.745835Z 0 [Warning] [MY-010068] [Server] CA certificate ca.pem is self signed.
cms-db_1          | 2024-01-26T07:40:53.745883Z 0 [System] [MY-013602] [Server] Channel mysql_main configured to support TLS. Encrypted connections are now supported for this channel.
cms-db_1          | 2024-01-26T07:40:53.784300Z 0 [Warning] [MY-011810] [Server] Insecure configuration for --pid-file: Location '/var/run/mysqld' in the path is accessible to all OS users. Consider choosing a different directory.
cms-db_1          | 2024-01-26T07:40:53.960078Z 0 [System] [MY-011323] [Server] X Plugin ready for connections. Bind-address: '::' port: 33060, socket: /var/run/mysqld/mysqlx.sock
cms-db_1          | 2024-01-26T07:40:53.960214Z 0 [System] [MY-010931] [Server] /usr/sbin/mysqld: ready for connections. Version: '8.0.36'  socket: '/var/run/mysqld/mysqld.sock'  port: 3306  MySQL Community Server - GPL.
cms-web_1         | Waiting for MySQL to start - max 300 seconds
cms-web_1         | MySQL started
cms-web_1         | Configuring MySQL cnf file
cms-web_1         | Updating settings.php
cms-web_1         | ERROR 2005 (HY000): Unknown MySQL server host 'mysql' (-2)
cms-web_1         | New install
cms-web_1         | Provisioning Database
cms-web_1         | ERROR 2005 (HY000): Unknown MySQL server host 'mysql' (-2)
cms-web_1         | Phinx by CakePHP - https://phinx.org.
cms-web_1         | 
cms-web_1         | using config file /var/www/cms/phinx.php
cms-web_1         | using config parser php
cms-web_1         | using migration paths 
cms-web_1         |  - /var/www/cms/db/migrations
cms-web_1         | warning no environment specified, defaulting to: production
cms-web_1         | using adapter mysql
cms-web_1         | using database cms
cms-web_1         | ordering by creation time

Ok. I can’t solve the problem.

I am guessing somewhere at the server there is a network configuration which is not compatible with the xibo containers.

Fortunately I could reset the changes. Now I have to investigate what the problem could be, that the web container can’t connect the mysql container.

Ok, meanwhile I know much more of the problem.
It is the same issue described here:

But I ran Version 2.3.x and after I did this mysql update:

I got the same problem as before. The cms-web Container can’t connect the cms-db Container with the alias “mysql” but over the IP and even with “cms-db” the mysql connection from cms-web to cms-db work fine.

For me it looks like the docker-compose “links” flag don’t work. May this is the reason?
“The --link flag is a legacy feature of Docker. It may eventually be removed.”

But how can I solve this?

OK - I found the solution.

I edit the docker-compose.yml file and add a aliases flag for the cms-db service. Now the cms-db Container is linked in the cms-web Container again with “mysql” and everything is working as before.

And the reason it took so long for me to find the solution was: I didn’t understand how to access the default network, because the examples I found always mention a concrete docker network. So I missed the keyword “default” and my tries failed.

    cms-db:
        image: mysql:5.7
        volumes:
            - "./shared/db:/var/lib/mysql:Z"
        environment:
            - MYSQL_DATABASE=cms
            - MYSQL_USER=cms
            - MYSQL_RANDOM_ROOT_PASSWORD=yes
        mem_limit: 1g
        env_file: config.env
        restart: always
        networks:
           default:
             aliases:
                - mysql
1 Like

Thank you very much, my English is bad, but your solution is beautiful