mysql --versioncommand, I saw the following:
# mysql --version mysql Ver 15.1 Distrib 5.5.37-MariaDB, for Linux (x86_64) using readline 5.1
mysqlcommand on the system, I received the error message shown below:
# mysql ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (111)
I checked to see if the mysqld service was running and found it was not.
# systemctl status mysqld.service mysqld.service Loaded: not-found (Reason: No such file or directory) Active: inactive (dead)
When I tried to start the service, it wouldn't start.
# service mysqld start Redirecting to /bin/systemctl start mysqld.service Failed to issue method call: Unit mysqld.service failed to load: No such file or directory. # systemctl start mysqld.service Failed to issue method call: Unit mysqld.service failed to load: No such file or directory.
I checked the contents of the
/etc/my.cnf file and saw the
[mysqld] datadir=/var/lib/mysql socket=/var/lib/mysql/mysql.sock # Disabling symbolic-links is recommended to prevent assorted security risks symbolic-links=0 # Settings user and group are ignored when systemd is used. # If you need to run mysqld under a different user or group, # customize your systemd unit file for mariadb according to the # instructions in http://fedoraproject.org/wiki/Systemd [mysqld_safe] log-error=/var/log/mariadb/mariadb.log pid-file=/var/run/mariadb/mariadb.pid # # include all files from the config directory # !includedir /etc/my.cnf.d
I checked for the existence of files and directories listed in that
file. I saw the following results for the locations for
# ls -ld /var/lib/mysql drwxr-xr-x. 19 mysql mysql 4096 Oct 14 23:46 /var/lib/mysql [root@localhost install]# ls -l /var/lib/mysql/mysql.sock srwxrwxrwx. 1 mysql mysql 0 Sep 29 15:05 /var/lib/mysql/mysql.sock # ls -l /var/log/mariadb/mariadb.log -rw-r-----. 1 mysql mysql 0 Oct 5 20:49 /var/log/mariadb/mariadb.log # ls -l /var/run/mariadb/mariadb.pid ls: cannot access /var/run/mariadb/mariadb.pid: No such file or directory
I didn't see any
mariadb.pid file, but I wouldn't expect it
to be created until the mysqld service successfully started.
When I checked the files in the
includedir directory, I saw
# ls -l /etc/my.cnf.d total 12 -rw-r--r--. 1 root root 295 Apr 15 2014 client.cnf -rw-r--r--. 1 root root 232 Apr 15 2014 mysql-clients.cnf -rw-r--r--. 1 root root 744 Apr 15 2014 server.cnf
So I didn't know why I was getting the "Can't connect to local MySQL server
through socket '/var/lib/mysql/mysql.sock'" message when I issued the
mysql nor why my attempt to start the mySQL service
failed with a "No such file or directory" message. Searching online, I
found a posting by
No mysqld or mysql.server after mariadb-server install to use
systemctl start mariadb.service. When I used that command, I
didn't see any error messages. I tried the
systemctl status mysqld
service after issuing the command, but still saw a error message for it.
But, when I then issued the
mysql command I received an "access
denied" message this time, which seemed reasonable, since I hadn't provided
the password for the root account when I issued the command..
# systemctl start mariadb.service # systemctl status mysqld service mysqld.service Loaded: not-found (Reason: No such file or directory) Active: inactive (dead) service.service Loaded: not-found (Reason: No such file or directory) Active: inactive (dead) # mysql ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO)
When I was using CentOS 5, I had MySQL rather than MariaDB and I didn't
know I needed to start the MariaDB RDBMS service on the CentOS 7 system using a
mariadb rather than
assumed I could reference mysqld to start the service.
The history behind the creation of MariaDB can be found in the history section of the Wikipedia article on MySQL. MariaDB was created by one of the cofounders of MySQL, Michael Widenius, after Oracle Corporation obtained rights to the MySQL software from Sun Microsystems.
To have the MariaDB service start automatically each time the system
boots, issue the command
systemctl enable mariadb.service.
After you have started the service, also issue the command
# mysql_secure_installation /usr/bin/mysql_secure_installation: line 379: find_mysql_client: command not found NOTE: RUNNING ALL PARTS OF THIS SCRIPT IS RECOMMENDED FOR ALL MariaDB SERVERS IN PRODUCTION USE! PLEASE READ EACH STEP CAREFULLY! In order to log into MariaDB to secure it, we'll need the current password for the root user. If you've just installed MariaDB, and you haven't set the root password yet, the password will be blank, so you should just press enter here. Enter current password for root (enter for none): ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO) Enter current password for root (enter for none): OK, successfully used password, moving on... Setting the root password ensures that nobody can log into the MariaDB root user without the proper authorisation. You already have a root password set, so you can safely answer 'n'. Change the root password? [Y/n] n ... skipping. By default, a MariaDB installation has an anonymous user, allowing anyone to log into MariaDB 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? [Y/n] 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? [Y/n] Y ... Success! By default, MariaDB 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? [Y/n] 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? [Y/n] Y ERROR 1146 (42S02) at line 1: Table 'mysql.servers' doesn't exist ... Failed! Cleaning up... All done! If you've completed all of the above steps, your MariaDB installation should now be secure. Thanks for using MariaDB!
I had it remove the anonymous account, since leaving it would be a security vulnerability. I also chose to disallow remote root login to MariaDB and the test database for the same reason.
I had copied the contents of the
from the hard drive of the prior CentOS 5 system to the new CentOS 7 system
to have all of the databases from the old system available on the new
system, so that appeared to be the reason that the
mysql_secure_installation, which can be found in
/usr/bin, did not accept my just hitting Enter for
the password initially. When I entered the root password for MySQL on the
old system, it was accepted. And I was able finally get a prompt where
I could enter SQL commands using that password with
mysql -u root -p
# mysql -u root -p Enter password: Welcome to the MariaDB monitor. Commands end with ; or \g. Your MariaDB connection id is 11 Server version: 5.5.37-MariaDB MariaDB Server Copyright (c) 2000, 2014, Oracle, Monty Program Ab and others. Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. MariaDB [(none)]>
So the 3 steps to enable and run MariaDB are as follows,
assuming it was previously installed during the initial setup
for the system or with
yum install mariadb mariadb-server:
systemctl start mariadb.service
systemctl enable mariadb.service
Created: Tuesday November 11, 2014