1.问题1：ORA-28040: No matching authentication protocol
解决办法：在sqlnet.ora添加如下项
[oracle@localhost admin]$ vi sqlnet.ora
NAMES.DIRECTORY_PATH= (TNSNAMES, EZCONsECT)
# sqlnet.ora Network Configuration File: /u01/app/oracle/product/12.2.0.1/db_1/network/admin/sqlnet.ora
# Generated by Oracle configuration tools.
NAMES.DIRECTORY_PATH= (TNSNAMES, EZCONNECT)
SQLNET.ALLOWED_LOGON_VERSION_CLIENT = 8
SQLNET.ALLOWED_LOGON_VERSION_SERVER = 8
2.问题2:明明账号密码是对的，但是提示：ORA-01017: invalid username/password; logon denied
解决办法：
重置下相关账号的密码
alter user hxl identified by oracle;