Troubleshooting of two MySQL problems in RedHatLinuxAS4

Problem 1: mysql logon error ERROR2002 (HY000): Can 'tconnecttolocalmysqlserverthroughsocket '/var/lib/mysql. sock '(2) solution: 1) default mysql. the sock file is in the/tmp directory. 2) Establish a soft connection, ln-s/tmp/mysql. sock/var/lib/my

Problem 1: An error occurred while logging on to mysql.
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/lib/mysql. sock' (2)
Solution:
1) The default mysql. sock file is in the/tmp directory.
2) Establish a soft connection, ln-s/tmp/mysql. sock/var/lib/mysql. sock
Problem 2: Timeout error occurred trying to start MySQL Daemon.
#/Etc/init. d/mysqld restart
Stopping mysql [OK]
Timeout error occurred trying to start MySQL Daemon. [failure]
However, mysql has actually started at this time, because the netstat-ln command is used to check that port 3306 has been started. mysql-u root-p password can also be used to connect to the database.

Solution:
Modify/etc/init. d/mysqld.
Create a dameon user in mysql, and then modify/etc/init. d/mysqld.
The procedure is as follows:
Let's take a look at how the/etc/init. d/mysqld STARTUP script works. Pay attention to the following section.
# If you 've removed anonymous users, this line must be changed
# Use a user that is allowed to ping mysqld.
Ping = "/usr/bin/mysqladmin-uUNKNOWN_MYSQL_USER ping"
# Spin for a maximum of ten seconds waiting for the server to come up
If [$ ret-eq 0]; then
For x in 1 2 3 4 5 6 7 8 9 10; do
If [-n "'$ ping 2>/dev/null'"]; then
Break;
Else
Sleep 1;
Fi
Done
If! ([-N "'$ ping 2>/dev/null'"]); then
Echo "Timeout error occurred trying to start MySQL
Daemon. "action $" Starting $ prog: "/bin/false
Else
Action $ "Starting $ prog:"/bin/true
Fi
Else
Action $ "Starting $ prog:"/bin/false
Fi
[$ Ret-eq 0] & touch/var/lock/subsys/mysqld
Return $ ret
 
We can see that the script determines whether mysql is started and uses the mysqladmin ping command.
To execute this command correctly, you must be able to log on to mysql. now some default accounts have been deleted, and other accounts have set a password (no password is set by default ). so it cannot connect to mysql.
So I used the following solution.
A) create an account without a password or any permissions.
B) Modify/etc/init. d/mysqld
The following are my specific operations:
# Mysql-u root-p passwd
Mysql> GRANT select ON test. * TO daemon @ localhost
Mysql> revoke select on test. * from daemon @ localhost
Vi open/etc/init. d/mysqld
Set the following line
Ping = "/usr/bin/mysqladmin-uUNKNOWN_MYSQL_USER ping"

Change
Ping = "/usr/bin/mysqladmin-udaemon ping"

Save and exit.
Restart mysql
#/Etc/init. d/mysqld restart
Stopping MySQL: [OK]
Starting MySQL: [OK]