This error is most very common in mysql which trigger due to numerous reasons
Check if mysql services are up and running
[root@tibero tibero]# ps -ef|grep -i 'mysql'
root 2096 2084 0 22:58 pts/0 00:00:00 /usr/bin/python /usr/bin/yum install mysql -y
root 2342 1 0 23:05 pts/0 00:00:00 /bin/sh /usr/bin/mysqld_safe --datadir=/var/lib/mysql --socket=/var/lib/mysql/mysql.sock --pid-file=/var/run/mysqld/mysqld.pid --basedir=/usr --user=mysql
mysql 2444 2342 0 23:05 pts/0 00:00:00 /usr/libexec/mysqld --basedir=/usr --datadir=/var/lib/mysql --user=mysql --log-error=/var/log/mysqld.log --pid-file=/var/run/mysqld/mysqld.pid --socket=/var/lib/mysql/mysql.sock
root 2467 2211 0 23:05 pts/0 00:00:00 /bin/sh /usr/bin/mysql_secure_installation
root 2543 2211 0 23:11 pts/0 00:00:00 grep -i mysql
Check if you have socket parameter specified in my.cnf file
[root@tibero tibero]# cat /etc/my.cnf
[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
user=mysql
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0
[mysqld_safe]
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid
Check if the file exist in /var/lib directory
[root@tibero tibero]# ls -lrt /var/lib/mysql/mysql.sock
srwxrwxrwx 1 mysql mysql 0 Jul 1 23:05 /var/lib/mysql/mysql.sock
Restart mysql service
[root@tibero tibero]# service mysqld restart
Stopping mysqld: [ OK ]
Initializing MySQL database: Installing MySQL system tables...
OK
Filling help tables...
OK
To start mysqld at boot time you have to copy
support-files/mysql.server to the right place for your system
PLEASE REMEMBER TO SET A PASSWORD FOR THE MySQL root USER !
To do so, start the server, then issue the following commands:
/usr/bin/mysqladmin -u root password 'new-password'
/usr/bin/mysqladmin -u root -h tibero password 'new-password'
Alternatively you can run:
/usr/bin/mysql_secure_installation
which will also give you the option of removing the test
databases and anonymous user created by default. This is
strongly recommended for production servers.
See the manual for more instructions.
You can start the MySQL daemon with:
cd /usr ; /usr/bin/mysqld_safe &
You can test the MySQL daemon with mysql-test-run.pl
cd /usr/mysql-test ; perl mysql-test-run.pl
Please report any problems with the /usr/bin/mysqlbug script!
[ OK ]
Starting mysqld: [ OK ]Try change mysql login password and login
[root@tibero tibero]# /usr/bin/mysqladmin -u root -h tibero password oracle
[root@tibero tibero]# mysql
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 7
Server version: 5.1.73 Source distribution
Copyright (c) 2000, 2013, 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>
Use telnet to connect to mysql port
[root@tibero ~]# telnet 127.0.0.1 3306
Check if the port 3306 is up
[root@tibero ~]# netstat -tupln|grep '3306'
tcp 0 0 0.0.0.0:3306 0.0.0.0:* LISTEN 2201/mysqld
