远程连接mysql提示：1251-client does not support authentication protocol requested by server

在mysql主机登录后

1.查看用户信息
select host,user,plugin,authentication_string from mysql.user;
1

备注：
host为 % 表示不限制ip
localhost表示本机使用
plugin非mysql_native_password 则需要修改密码

2.修改用户密码

mysql> ALTER USER 'root'@'%' IDENTIFIED WITH mysql_native_password BY '123456';   

　　　 # ALTER USER 'root'@'%' IDENTIFIED WITH mysql_native_password BY 'newpassword'; #更新一下用户的密码 root用户密码为newpassword
Query OK, 0 rows affected (0.10 sec)

mysql> SELECT User, Host FROM mysql.user;
+------------------+-----------+
| User | Host |
+------------------+-----------+
| root | % |
| debian-sys-maint | localhost |
| mysql.infoschema | localhost |
| mysql.session | localhost |
| mysql.sys | localhost |
| root | localhost |
+------------------+-----------+
6 rows in set (0.01 sec)

mysql> select host,user,plugin,authentication_string from mysql.user;
+-----------+------------------+-----------------------+------------------------------------------------------------------------+
| host | user | plugin | authentication_string |
+-----------+------------------+-----------------------+------------------------------------------------------------------------+
| % | root | mysql_native_password | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 |
| localhost | debian-sys-maint | caching_sha2_password | $A$005$&[CW4 j.|1mV 0)A(0cQoGIOyhwwb4bie4l0a2MXmRIoI7wJLP4Ik2gr9O0u8 |
| localhost | mysql.infoschema | caching_sha2_password | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| localhost | mysql.session | caching_sha2_password | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| localhost | mysql.sys | caching_sha2_password | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| localhost | root | mysql_native_password | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 |
+-----------+------------------+-----------------------+------------------------------------------------------------------------+
6 rows in set (0.00 sec)

mysql> FLUSH PRIVILEGES;