Remote accessing mysql server running on docker container - mysql

Question

How to access the MySQL server running on a Docker container in a remote machine.
Here is my dockerfile:
MAINTAINER debu_bbsr#yahoo.com
RUN apt-get update \
&& DEBIAN_FRONTEND=noninteractive apt-get install -y mysql-server \
&& sed -i "s/127.0.0.1/0.0.0.0/g" /etc/mysql/mysql.conf.d/mysqld.cnf \
&& mkdir /var/run/mysqld \
&& chown -R mysql:mysql /var/run/mysqld
VOLUME ["/var/lib/mysql"]
EXPOSE 3306
CMD ["mysqld_safe"]
I created an image:
sudo docker build -t deb_mysql_image .
Run the Docker container with the above image:
sudo docker run -i -t -d -p 3306:3306 --name mysql_deb_container deb_mysql_image
Enter into the MySQL container:
`k8smaster#k8smaster:~/debashish$ sudo docker exec -it mysql_deb_container mysql`
Create different users and database:
mysql> create user debashish identified by 'debashish';
mysql> create user debmysql identified by 'debmysql';
mysql> create database debdb;
mysql> use debdb;
Grant privileges to the users and create a table:
mysql> GRANT ALL PRIVILEGES ON *.* TO 'debashish' WITH GRANT OPTION;
CREATE TABLE debtbl1 (name VARCHAR(20), address VARCHAR(50));
Populate the table:
insert into debtbl1 values('Debashish', 'Shanghai');
insert into debtbl1 values('Debu', 'Livingston, Shanghai');
Now access the contents of the above MySQL table from a remote machine with the MySQL client:
k8snode1#k8snode1:~$ mysql -u 'debashish' -p -h 10.10.10.2 -P 3306 -D debdb
Enter password
"Sometimes" I encounter the issue -
ERROR 1045 (28000): Access denied for user
Anything am I missing to make it a robust system so I dont encounter "sometimes" the above error.

Answer 1

Most likely your user doesn't have permissions to access from that server, either grant privileges for that specific server or globally.
Run:
GRANT ALL PRIVILEGES ON *.* TO 'debashish'#'%' WITH GRANT OPTION;
FLUSH PRIVILEGES;

Answer 2

The issue was that - whenever a Pod was restarted, all the privileges assigned to the Mysql DB also gets erased.
Hence the solution was to - write a shell script that will be:
1. Executed when the Pod is started/scaled-in/container is started.
2. The shell script automatically creates the database and users.
3. Shell script then grants permission to the users for the DB.