[Mysql] restoring mysql and & amp; quot; Accessdeniedforuser & amp; #39; root & amp; #39 ;@& amp; #39; IP & amp; after windows is reinstalled; #39; & amp; quot; troubleshooting

[Mysql] restore mysql and & quot; Accessdeniedforuser & #39; root & #39 ;@&# 39; IP & #39; & quot; troubleshooting after windows is reinstalled

Mysql databases are actually green software and can still be used after the system is reinstalled.

1. Reload the system and keep the original mysql installation directory and data directory.

2. Create a batch file to start mysql: [run. bat] the file is stored in the bin under the mysql installation directory.

Mysqld.exe -- defaults-file = ../my-default.ini -- console

3. run. bat.

If the following error occurs during database connection: "Access denied for user 'root' @ 'IP '"

1. log on to the system as an administrator, stop the mysql service, or end the mysqld process.
2. Enter the command line and go to the mysql installation directory. Assume that the installation directory is d: \ mysql \, and CMD enter the command line.
3. Run d: \ mysql \ bin \ mysqld-nt -- skip-grant-tables to start mysql and disable permission check.

4. Run d: \ mysql \ bin \ mysqladmin-u root flush-privileges password "newpassword" to reset the root password.
5. Restart the mysql service.

In Linux, the following methods can be used:

Method 1:
#/Etc/init. d/mysql stop
# Mysqld_safe -- user = mysql -- skip-grant-tables -- skip-networking &
# Mysql-u root mysql
Mysql> UPDATE user SET Password = PASSWORD ('newpassword') where USER = 'root ';
Mysql> flush privileges;
Mysql> quit
#/Etc/init. d/mysql restart
# Mysql-uroot-p
Enter password: <Enter the new password newpassword>
Mysql>
Method 2:
Directly use the username and password provided in the [client] section of the/etc/mysql/debian. cnf file:
# Mysql-udebian-sys-maint-p
Enter password: <Enter the password in the [client] section>
Mysql> UPDATE user SET Password = PASSWORD ('newpassword') where USER = 'root ';
Mysql> flush privileges;
Mysql> quit
# Mysql-uroot-p
Enter password: <Enter the new password newpassword>
Mysql>

Zookeeper