Mdthbs

My goal is to have MariaDB 10.1 and MySQL 8 on the same Ubuntu 18.04 server.

I was able to setup MySQL 8 successfully, and got stuck almost at the end while setting up MariaDB following this guide:

https://mariadb.com/kb/en/library/installing-mariadb-alongside-mysql/

Basically this is what I did:

1. downloaded mariadb for linux


2. copied the extracted folder to /opt/mariadb


3. created /opt/mariadb-data folder


4. chown'ed by mariadb user (freshly created)


5. copied a my.cnf to /opt/mariadb-data and edited port number and user, basedir and datadir. copied a mysql.service file to /etc/init.d/mariadb and edited it


6. ran setup script


7. tried starting, and got this error:

Warning: The unit file, source configuration file or drop-ins of mariadb.service changed on disk. Run 'systemctl daemon-reload' to reload

● mariadb.service - LSB: start and stop MySQL

   Loaded: loaded (/etc/init.d/mariadb; generated)

   Active: failed (Result: exit-code) since Thu 2019-08-29 23:27:12 EDT; 2s ago

     Docs: man:systemd-sysv-generator(8)

  Process: 35976 ExecStop=/etc/init.d/mariadb stop (code=exited, status=0/SUCCESS)

  Process: 36610 ExecStart=/etc/init.d/mariadb start (code=exited, status=1/FAILURE)

    Tasks: 28 (limit: 4563)

   CGroup: /system.slice/mariadb.service

           ├─33699 /bin/sh /opt/mariadb/bin/mysqld_safe --defaults-file=/opt/mariadb-data/my.cnf --datadir=/opt/mariadb/data --pid-file=/o

           └─33830 /opt/mariadb/bin/mysqld --defaults-file=/opt/mariadb-data/my.cnf --basedir=/opt/mariadb --datadir=/opt/mariadb/data --p



Aug 29 23:27:11 dev03.example.com systemd[1]: Starting LSB: start and stop MySQL...

Aug 29 23:27:11 dev03.example.com mariadb[36610]: Starting MySQL

Aug 29 23:27:11 dev03.example.com mariadb[36610]: .190829 23:27:11 mysqld_safe Logging to '/opt/mariadb-data/dev03.example.com.err'.

Aug 29 23:27:11 dev03.example.com mariadb[36610]: 190829 23:27:11 mysqld_safe A mysqld process already exists

Aug 29 23:27:12 dev03.example.com mariadb[36610]:  *

Aug 29 23:27:12 dev03.example.com systemd[1]: mariadb.service: Control process exited, code=exited status=1

Aug 29 23:27:12 dev03.example.com systemd[1]: mariadb.service: Failed with result 'exit-code'.

Aug 29 23:27:12 dev03.example.com systemd[1]: Failed to start LSB: start and stop MySQL.

Here's the important part of the configuration I've set for my.cnf following the tutorial link.

Create a new my.cnf in /opt/mariadb from support files:

[root@mariadb-near-mysql opt]# cp mariadb/support-files/my-medium.cnf mariadb-data/my.cnf

[root@mariadb-near-mysql opt]# chown mariadb:mariadb mariadb-data/my.cnf

Edit the file /opt/mariadb-data/my.cnf and add custom paths, socket, port, user and the most important of all: data directory and base directory. Finally the file should have at least the following:

[client]

port        = 3307

socket      = /opt/mariadb-data/mariadb.sock



[mysqld]

datadir         = /opt/mariadb-data

basedir         = /opt/mariadb

port        = 3307

socket      = /opt/mariadb-data/mariadb.sock

user            = mariadb

Copy the init.d script from support files in the right location:

[root@mariadb-near-mysql opt]# cp mariadb/support-files/mysql.server /etc/init.d/mariadb

[root@mariadb-near-mysql opt]# chmod +x /etc/init.d/mariadb

Edit /etc/init.d/mariadb replacing mysql with mariadb as below:

- # Provides: mysql

+ # Provides: mariadb

- basedir=

+ basedir=/opt/mariadb

- datadir=

+ datadir=/opt/mariadb-data

- lock_file_path="$lockdir/mysql"

+ lock_file_path="$lockdir/mariadb"

The trickiest part will be the last changes to this file. You need to tell mariadb to use only one cnf file. In the start section after $bindir/mysqld_safe add --defaults-file=/opt/mariadb-data/my.cnf. Finally the lines should look like:



# Give extra arguments to mysqld with the my.cnf file. This script

# may be overwritten at next upgrade.

$bindir/mysqld_safe --defaults-file=/opt/mariadb-data/my.cnf --datadir="$datadir" --pid-file="$mysqld_pid_file_path" $other_args >/dev/null 2>&1 &

The same change needs to be made to the mysqladmin command below in the wait_for_ready() function so that the mariadb start command can properly listen for the server start. In the wait_for_ready() function, after $bindir/mysqladmin add --defaults-file=/opt/mariadb-data/my.cnf. The lines should look like:

What can I do to change the mysqld process name for MariaDB or can I avoid conflict another way?