setting mysql root password in CentOS 7

Question

How can I log into the mysql 5.6 command line client and reset the root password in Centos7?

I read the following at this link, but it does not work:

1) sudo service mysqld stop
2) sudo service mysqld startsos
3) mysql -u root
4) Now you will be at mysql prompt. Here type:-
4.1) UPDATE mysql.user SET Password=PASSWORD('NewPassHere') WHERE User='root';
4.2) FLUSH PRIVILEGES;
4.3) quit;
5) sudo service mysqld restart  

Step 1) above results in:

[root@localhost ~]# sudo service mysqld stop
Redirecting to /bin/systemctl stop  mysqld.service
Failed to issue method call: Unit mysqld.service not loaded.

Step 3) above results in:

-bash: syntax error near unexpected token `('

When I change step 3 to UPDATE mysql.user SET Password='NewPassHere' WHERE User='root';, I get the following error:

bash: UPDATE: command not found...

I do seem to be able to get into mysql when i type su - to become root and then type mysql - u root at the next prompt. But then the above 5 step commands do not work, even when I remove the word sudo and/or replace the word service with systemctl. How can I get working access to the mysql 5.6 command line in CentOS 7, starting with setting the root password?

Answer 1

To install latest MySql 5.7 on RHEL/Centos 7. There are few steps follows-:

Step 1-: Add the below EPEL Repository

$ sudo rpm -iUvh http://dev.mysql.com/get/mysql57-community-release-el7-7.noarch.rpm

Step 2-: Install the MySql Server using below yum installer.

$ sudo yum install mysql-server 

Step 3-: Add to system Startup and start the Mysql Server.

$ sudo systemctl enable mysqld
$ sudo systemctl start mysqld

Step 4-: Reset the MySql server root password.

sudo grep 'temporary password' /var/log/mysqld.log

Output Something like-:

10.744785Z 1 [Note] A temporary password is generated for root@localhost: o!5y,oJGALQa

Use the above password during reset mysql_secure_installation process.

$ sudo mysql_secure_installation
Securing the MySQL server deployment.

Enter password for user root: 
The 'validate_password' plugin is installed on the server.
The subsequent steps will run with the existing configuration
of the plugin.
Using existing password for root.

Estimated strength of the password: 100 
Change the password for root ? ((Press y|Y for Yes, any other key for No) : y

New password: 

Re-enter new password: 

Estimated strength of the password: 100 
Do you wish to continue with the password provided?(Press y|Y for Yes, any other key for No) : y
By default, a MySQL installation has an anonymous user,
allowing anyone to log into MySQL without having to have
a user account created for them. This is intended only for
testing, and to make the installation go a bit smoother.
You should remove them before moving into a production
environment.

Remove anonymous users? (Press y|Y for Yes, any other key for No) : y
Success.


Normally, root should only be allowed to connect from
'localhost'. This ensures that someone cannot guess at
the root password from the network.

Disallow root login remotely? (Press y|Y for Yes, any other key for No) : y
Success.

By default, MySQL comes with a database named 'test' that
anyone can access. This is also intended only for testing,
and should be removed before moving into a production
environment.


Remove test database and access to it? (Press y|Y for Yes, any other key for No) : y
 - Dropping test database...
Success.

 - Removing privileges on test database...
Success.

Reloading the privilege tables will ensure that all changes
made so far will take effect immediately.

Reload privilege tables now? (Press y|Y for Yes, any other key for No) : y
Success.

All done!

You have successfully reset the root password of MySql Server.

Step 5-: Use the below command to check the mysql server connecting or not.

$ mysql -u root -p

Output-:

Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 9
Server version: 5.7.12 MySQL Community Server (GPL)

Copyright (c) 2000, 2016, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql>

See my article: install-latest-mysql-5-7-rhelcentos-7

Answer 2

Sometimes you can clobber your configuration. As such, it's easier to start over, as if the package had never been installed. In your case, we are looking at MySQL.

1. We use Yum to Remove MySQL, like so:
   yum remove mysql mysql-server
2. With MySQL removed, we can safely backup the configuration:
   mv /var/lib/mysql /var/lib/mysql_old_backup
   If you'd rather remove it, issue:
   rm -vR /var/lib/mysql
3. Now we can safely reinstall MySQL, using the default configuration that is included in the package from the Official MySQL repository (we need wget to fetch the rpm that will update your repos):
   yum install wget
4. Now download and install the repository:
   wget http://repo.mysql.com/mysql-community-release-el7-5.noarch.rpm && rpm -ivh mysql-community-release-el7-5.noarch.rpm
5. Verify the repositories are installed:
   ls -1 /etc/yum.repos.d/mysql-community*
6. Issue the actual install command (This will replace the mysql-server in the CentOS repository with the official package from upstream MySQL):
   yum install mysql-server
7. Use the script provided to set the root password, now that we have a fresh install again: mysql_secure_installation
   If you ever need to set the password after using the script, use:
   mysql -u root
8. Now you can use the standard commands from systemctl, part of systemd to Start and Stop the daemon like so:
   systemctl start mysqld

---

References

1. How to Remove MySQL Completely from Linux System - CentOS
2. How to install MySQL Server 5.6 on CentOS 7 / RHEL 7

Answer 3

If you can get into MySQL when using the command:

mysql -u root

Then you already have access to MySQL, you will either not have a password set for the "root" user (most likely) or you may have a password set in a configuration file for MySQL such as /etc/my.cnf.

If you want to reset your MySQL root password then you should be able to run:

$ mysql_secure_installation

Answer 4

It is probably because the 'restart' is not killing the MySQL started in the sos mode by 'startsos' and port 3306 (or wherever it is running) is occupied. After the 4th step, please try these:

$ sudo service mysqld stop
$ ps -ef | grep mysql

Now, from the output of ps, if you don't see any mysql processes running, then start MySQL using the below command. If you see a mysql process running, then start MySQL after killing the mysql process.

$ sudo service mysqld start

Answer 5

if you are here for, just the password, use

sudo grep 'temporary password' /var/log/mysqld.log

password will be at the end of the string, example-

2021-09-20T08:57:32.734131Z 1 [Note] A temporary password is generated for root@localhost: tgo;40Yj;_xy3