报错no matching authentication protocol

vi /usr/local/products/oracle12c/network/admin/sqlnet.ora
#添加如下内容

SQLNET.ALLOWED_LOGON_VERSION=8

链接报错 listener does currently know of server requested in connect descriptor

 vi /usr/local/products/oracle12c/network/admin/samples/tnsnames.ora

#添加如下内容，修改对应数据库服务名和本机IP地址
3.10 =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.3.10)(PORT = 1521))
    )
    (CONNECT_DATA =
      (SERVICE_NAME = CDB1)
    )
  )

忘了用户密码，修改用户密码 
alter user system identified by 123456;

#报错- lost connection to mysql server at 'reading initial communication packet',system error:0 

vim /etc/my.cnf 中的[mysqld]下添加skip-name-resolve

#报错1698  Access denied for user *@*
 mysql -u root -p
#进行远程连接授权
GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' WITH GRANT OPTION;
GRANT ALL PRIVILEGES ON *.* TO 'zabbix'@'%' WITH GRANT OPTION;
flush privileges;
use zabbix;
GRANT ALL PRIVILEGES ON *.* TO 'zabbix'@'%'IDENTIFIED BY '111111' WITH GRANT OPTION;
GRANT ALL PRIVILEGES ON *.* TO 'root'@'%'IDENTIFIED BY '111111' WITH GRANT OPTION;
flush privileges;