1. 獲取可用用戶(hù)名

$ sudo cat /etc/mysql/debian.cnf

可以看到該文件中的內(nèi)容

[client]
host     = localhost
user     = debian-sys-maint
password = ********
socket   = /var/run/mysqld/mysqld.sock
[mysql_upgrade]
host     = localhost
user     = debian-sys-maint
password = ********
socket   = /var/run/mysqld/mysqld.sock

2. 使用該用戶(hù)名進(jìn)入mysql

$ mysql -u debian-sys-maint -p
Enter password:

3. 修改mysql數(shù)據(jù)庫(kù)中的user表

用戶(hù)名和密碼存在該表中

$ update mysql.user set authentication_string=password('123qwe') \
>   where user='root'

4. 重啟mysql

$ service mysql restart