export DB_PWD=secret
export installDir=/opt
export dataDir=$installDir/mysql/data
export binDir=$installDir/mysql/bin 
declare BIT_APP='bitnami-mysql-8.0.15-0-linux-x64-installer.run'

cd /tmp
wget https://downloads.bitnami.com/files/stacks/mysql/8.0.15-0/$BIT_APP

chmod +x $BIT_APP               # makes file executable

$BIT_APP --mode text            # install from command line

# MySQL version with the command 
$installDir/mysql/bin/mysqladmin --version 
$installDir/mysql/bin/mysqld --version

cat $installDir/mysql/my.cnf           # The MySQL configuration file
 
cat $installDir/mysql/bitnami/my.cnf   # Some configuration overrides  

# The MySQL .pid file allows other programs to find out the PID of a running script.
cat $installDir/mysql/data/mysqld.pid

# MySQL clients can connect to the server in the local machine using an Linux socket file 
cat $installDir/mysql/tmp/mysql.sock


# You can connect to the MySQL database from the same computer where it is installed with the mysql client tool.
cd $binDir
./mysql -u root -p$DB_PWD

# To back up all the databases, create a dump file using the mysqldump tool.
mysqldump -A -u root -p$DB_PWD > backup.sql

# Once you have the backup file, you can restore it with a command like the one below:
mysql -u root -p$DB_PWD < backup.sql

# The main log file is created at 
tail -n 100 $installDir/mysql/data/mysqld.log

# Start the MySQL database with the following command:
mysqld --skip-grant-tables --user=mysql --pid-file=$dataDir/mysqld.pid 
 --skip-external-locking --port=3306 --sock=$installDir/bitnami/mysql/tmp/mysql.sock

# Open a new console and try to log in the database:
mysql -u root -p 

# In this case, the error was related to the mysql.user table. Run these commands:
 mysql> use mysql;
 mysql> repair table user;
 mysql> check table user;
 mysql> exit;

###  How To Secure Your Server?
# Once you have created a new database and user for your application, connect to your MySQL server and follow these recommendations:
# Remove anonymous users:

 mysql> DELETE FROM mysql.user WHERE User='';

# Remove the test database and access to it:
 mysql> DROP DATABASE test;
 mysql> DELETE FROM mysql.db WHERE Db='test' OR Db='test\\_%';

# Disallow root login remotely:
 mysql> DELETE FROM mysql.user WHERE User='root' AND Host NOT IN ('localhost', '127.0.0.1', '::1');

# Do not forget to reload the privileges tables to apply the changes:
 mysql> FLUSH PRIVILEGES;

# Change your root user password.

# If you do not need remote access, uncomment the line

 #bind-address=127.0.0.1
in the MySQL configuration file to only listen for connections on the local machine. Restart the server once done.