Problems installing mysql in ubuntu 18.04

Question

I have installed mysql since upgrading the operating system. But there seems to be a problem with the root password. I have tried to fix this in many ways on the web, so far it has not been successful.

systemctl status mysql.service give:

● mysql.service - MySQL Community Server
   Loaded: loaded (/lib/systemd/system/mysql.service; enabled; vendor preset: enabled)
   Active: failed (Result: exit-code) since Wed 2018-05-02 16:57:24 +07; 13s ago
  Process: 6172 ExecStartPre=/usr/share/mysql/mysql-systemd-start pre (code=exited, status=217/USER)
Thg 5 02 16:57:24 thiennguyen systemd[1]: mysql.service: Service hold-off time  over, scheduling restart.
Thg 5 02 16:57:24 thiennguyen systemd[1]: mysql.service: Scheduled restart job,  restart counter is at 5.
Thg 5 02 16:57:24 thiennguyen systemd[1]: Stopped MySQL Community Server.
Thg 5 02 16:57:24 thiennguyen systemd[1]: mysql.service: Start request repeated too quickly
Thg 5 02 16:57:24 thiennguyen systemd[1]: mysql.service: Failed with result 'exit-code'.
Thg 5 02 16:57:24 thiennguyen systemd[1]: Failed to start MySQL Community Server

journalctl -xe give: http://codepad.org/6EbGVu2Q

mysql_secure_installation give:

Securing the MySQL server deployment.
Enter password for user root: 
Error: Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2)

mysql -u root -p give:

Enter password: 
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2)

Especially when I install, mysql does not require setting password for root and i have reinstalled many times. Maybe the problem is old, but I have found many ways on the network but can not solve, so look forward to the help.

Answer 1

The answer marked as correct is technically not right. Ubuntu 18.04 uses sockets for authorization and not passwords!!

( https://websiteforstudents.com/mariadb-installed-without-password-prompts-for-root-on-ubuntu-17-10-18-04-beta/ )

For me logging in was as simple as:

sudo  mysql -u root      

I feel whoever is responsible for this "feature" really dropped the ball. There should have been a message stating that Ubuntu no longer used passwords when attempting to run mysql. this was a really drastic change in functionality.

Answer 2

You have to change the old password of MySQL at the time of secure installation. If you don't remember the old password try following way via root privilege:-

Stop the MySQL service.

service mysql stop

Start MySQL without password and permission checks.

mysqld_safe --skip-grant-tables &

Connect to MySQL

mysql -u root mysql

Run following commands to set a new password for root user.

UPDATE user SET password=PASSWORD('NEW_PASSWORD') WHERE user='root';
FLUSH PRIVILEGES;
service mysql restart

Some new version not support above UPDATE query try to use below

ALTER USER 'root'@'localhost' IDENTIFIED BY 'MyNewPass';

Answer 3

I'm aware about this problem and when used 16.04 it never happened. And in 18.04, i just tried to use it to resolve.

sudo mysql_secure_installation

In this case, i can set my password, but it does not work

And that code does not solve the problem.

UPDATE user SET password=PASSWORD('NEW_PASSWORD') WHERE user='root';

Answer 4

After the installation just:

1.  sudo mysql

   (yes, no user no pass)

2. You are now in the mysql console:

    ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY 'my_new_pass';

3. FLUSH PRIVILEGES;

4. That's it. You can now enter the console next time as usual:

    mysql -u root -p my_new_pass

Answer 5

I tried for about last 24 hours to get rid of those errors and migrate from 16.04 to 18.04 with the same database, but none of all web pages I looked helped me. It was a hell.

Trying systemctl status mysql.service and journalctl -xe was a dead end - no clues.

But the error:

Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2)

lead me to understanding, that mysql-server on 18.04 has a little bit different structure. During installation I had many times seen file like: /etc/mysql/FROZEN.

And only I deeply read it through I understand, that my mistake was coming from different versions of MySQL. It said that I initiated downgrade (from mysql-server-5.7 to mysql-server-5.6), despite I was sure that I did not do it, as I was installing mysql-server-5.7.

The only solution what worked for me was: deleting all files (and databases) from /var/lib/mysql manually and reinstalling mysql-server and mysql-client

I copied them to different location, but than I was unable to restore them. So, the problem was in databases, what could not be migrated. And I also could not find mysql-server-5.6 for Ubuntu 18.04 (I read, that some guy did it by manually compiling). Luckily it was made on test server, so nothing worth were lost. But anyway, next time I will have MySQL db backup before Ubuntu version migrating and make clean install, rather than trying to hold existing databases .

Answer 6

I also had many problems with both MySQL and MariaDB (ubuntu 18.04). I could not get MariaDB to work. I both using instructions at How to forcefully remove MySQL and MariaDB from Ubuntu 16.04, without `apt-get` and `dpkg`?

$ dpkg --list|grep -i mysql 

and

$ dpkg --list|grep -i mariadb

$ dpkg -remove --force-remove-reinstreq <package-list>

Then installed MySQL as described at https://dev.mysql.com/doc/mysql-apt-repo-quick-guide/en/

Works well now, even after a reboot. Don't know why this solution is not more widely spread!