Mysql root user initial password reset

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

Sort date (newest date)  

You may see something like this;

[root@SERVER ~]# grep 'temporary password' /var/log/mysqld.log  2016-01-16T18:07:29.688164Z 1 
[Note] A temporary password is generated for root@localhost: O,k5.marHfFu  2016-01-22T13:14:17.974391Z 1 
[Note] A temporary password is generated for root@localhost: b5nvIu!jh6ql  2016-01-22T15:35:48.496812Z 1 
[Note] A temporary password is generated for root@localhost: (B*=T!uWJ7ws  2016-01-22T15:52:21.088610Z 1 
[Note] A temporary password is generated for root@localhost: %tJXK7sytMJV  2016-01-22T16:24:41.384205Z 1 
[Note] A temporary password is generated for root@localhost: lslQDvgwr3/S  2016-01-22T22:11:24.772275Z 1 
[Note] A temporary password is generated for root@localhost: S4u+J,Rce_0t 

[root@SERVER ~]# mysql_secure_installation  

Securing the MySQL server deployment.

Enter password for user root:     The existing password for the user account root has expired. Please set a new password. 
New password:    
Re-enter new password:  

If you see it says

... Failed! Error: Your password does not satisfy the current policy requirements 
 That means your password needs to have a character such as ! . # - etc...  mix characters well, upper case, 
lower case, ! . , # etc...    New password:     Re-enter new password:   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!   [root@SERVER ~]# mysql -u root -p  Enter password:   Welcome to the MySQL monitor.  Commands end with ; or \g.  Your MySQL connection id is 11  Server version: 5.7.10 MySQL Community Server (GPL)