mysql5.7密碼修改 · 個人筆記

為了加強安全性，MySQL5.7為root用戶隨機生成了一個密碼，在error log中，關于error log的位置，如果安裝的是RPM包，則默認是/var/log/mysqld.log。一般可通過log_error設置 ~~~ mysql> select @@log_error; +---------------------+ | @@log_error | +---------------------+ | /var/log/mysqld.log | +---------------------+ 1 row in set (0.00 sec) ~~~ faNl:Pt._7&; 可通過# grep "password" /var/log/mysqld.log 命令獲取MySQL的臨時密碼 2016-01-19T05:16:36.218234Z 1 [Note] A temporary password is generated for root@localhost: waQ,qR%be2(5 更改密碼： ~~~ SET PASSWORD = PASSWORD('newpasswd'); ~~~ 用該密碼登錄到服務端后，必須馬上修改密碼，不然會報如下錯誤： ~~~ mysql> select user(); ERROR 1820 (HY000): You must reset your password using ALTER USER statement before executing this statement. ~~~ 如果只是修改為一個簡單的密碼，會報以下錯誤： ~~~ mysql> ALTER USER USER() IDENTIFIED BY '12345678'; ERROR 1819 (HY000): Your password does not satisfy the current policy requirements ~~~ 這個其實與validate_password_policy的值有關。 validate_password_policy有以下取值： Policy Tests Performed 0 or LOW Length 1 or MEDIUM Length; numeric, lowercase/uppercase, and special characters 2 or STRONG Length; numeric, lowercase/uppercase, and special characters; dictionary file 默認是1，即MEDIUM，所以剛開始設置的密碼必須符合長度，且必須含有數字，小寫或大寫字母，特殊字符。有時候，只是為了自己測試，不想密碼設置得那么復雜，譬如說，我只想設置root的密碼為123456。必須修改兩個全局參數：首先，修改validate_password_policy參數的值 ~~~ mysql> set global validate_password_policy=0; Query OK, 0 rows affected (0.00 sec) ~~~ 這樣，判斷密碼的標準就基于密碼的長度了。這個由validate_password_length參數來決定。 ~~~ mysql> select @@validate_password_length; +----------------------------+ | @@validate_password_length | +----------------------------+ | 8 | +----------------------------+ 1 row in set (0.00 sec) ~~~ validate_password_length參數默認為8，它有最小值的限制，最小值為： validate_password_number_count, validate_password_special_char_count, validate_password_mixed_case_count, 其中，validate_password_number_count指定了密碼中數據的長度，validate_password_special_char_count指定了密碼中特殊字符的長度，validate_password_mixed_case_count指定了密碼中大小字母的長度。這些參數，默認值均為1，所以validate_password_length最小值為4，如果你顯性指定validate_password_length的值小于4，盡管不會報錯，但validate_password_length的值將設為4。 ~~~ mysql> select @@validate_password_length; +----------------------------+ | @@validate_password_length | +----------------------------+ | 4 | +----------------------------+ 1 row in set (0.00 sec) mysql> select @@validate_password_mixed_case_count; +--------------------------------------+ | @@validate_password_mixed_case_count | +--------------------------------------+ | 1 | +--------------------------------------+ 1 row in set (0.00 sec) mysql> set global validate_password_mixed_case_count=2; Query OK, 0 rows affected (0.00 sec) mysql> select @@validate_password_mixed_case_count; +--------------------------------------+ | @@validate_password_mixed_case_count | +--------------------------------------+ | 2 | +--------------------------------------+ 1 row in set (0.00 sec) mysql> select @@validate_password_length; +----------------------------+ | @@validate_password_length | +----------------------------+ | 6 | +----------------------------+ 1 row in set (0.00 sec) ~~~ 當然，前提是validate_password插件必須已經安裝，MySQL5.7是默認安裝的。那么如何驗證validate_password插件是否安裝呢？可通過查看以下參數，如果沒有安裝，則輸出將為空。 ~~~ mysql> SHOW VARIABLES LIKE 'validate_password%'; +--------------------------------------+-------+ | Variable_name | Value | +--------------------------------------+-------+ | validate_password_dictionary_file | | | validate_password_length | 6 | | validate_password_mixed_case_count | 2 | | validate_password_number_count | 1 | | validate_password_policy | LOW | | validate_password_special_char_count | 1 | +--------------------------------------+-------+ 6 rows in set (0.00 sec) ~~~