Oracle用户密码认证方式

oracle用户有两种认证方式：

• 操作系统认证（要求该用户属于本地DBA组，然后通过操作系统认证登录oracle，从而启动数据库)
• 密码文件认证

oracle使用哪种认证方式决定在于两个参数:

1.remote_login_passwordfile=none|exclusive|shared

• none:不使用密码文件认证。如果选择了这个值，就相当于屏蔽了密码文件的内容了。
• exclusive:要密码文件认证，自己独占使用(默认值)
• shared:要密码文件认证，不同实例dba用户可以共享密码文件

2.位于$ORACLE_HOME/network/admin/sqlnet.ora

SQLNET.AUTHENTICATION_SERVICES=none|all|nts

• none:关闭操作系统认证，只能密码认证
• all:用于linux/unix平台，关闭本机密码文件认证，采用操作系统认证
• nts:用于windows平台

测试远程登录的时候密码文件丢失情况

$ rm -rf $ORACLE_HOME/dbs/orapw$ORACLE_SID

$ sqlplus sys/mypna123@userdata as sysdba

SQL*Plus: Release 10.2.0.4. - Production on Tue Sep  :: 

Copyright (c) , , Oracle.  All Rights Reserved.

ERROR:
ORA-: insufficient privileges

Enter user-name: 

$ orapwd file=orapw$ORACLE_SID password=mypna123 entries=

$ sqlplus sys/mypna123@userdata as sysdba

SQL*Plus: Release 10.2.0.4. - Production on Tue Sep  :: 

Copyright (c) , , Oracle.  All Rights Reserved.

Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.4. - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

SYS@userdata>

可以看到默认配置下,丢失密码文件后,不可以远程登录数据库,只可以本地系统认证后登录数据库

测试remote_login_passwordfile为exclusive,AUTHENTICATION_SERVICES为none的情况

SYS@userdata>show parameter remote_login_passwordfile;

NAME                     TYPE                   VALUE
------------------------------------ --------------------------------- ------------------------------
remote_login_passwordfile         string                   EXCLUSIVE

$ echo "SQLNET.AUTHENTICATION_SERVICES=NONE" >> $ORACLE_HOME/network/admin/sqlnet.ora

$ sqlplus / as sysdba

SQL*Plus: Release 10.2.0.4. - Production on Tue Sep  :: 

Copyright (c) , , Oracle.  All Rights Reserved.

ERROR:
ORA-: insufficient privileges

Enter user-name:

$ sqlplus sys/mypna123@userdata as sysdba

SQL*Plus: Release 10.2.0.4. - Production on Tue Sep  :: 

Copyright (c) , , Oracle.  All Rights Reserved.

Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.4. - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

SYS@userdata>

可以看到在remote_login_passwordfile为exclusive,AUTHENTICATION_SERVICES为none的情况下,数据库只能使用密码文件认证方式

测试remote_login_passwordfile为exclusive,AUTHENTICATION_SERVICES为all的情况

SYS@userdata>show parameter remote_login_passwordfile;

NAME                     TYPE                   VALUE
------------------------------------ --------------------------------- ------------------------------
remote_login_passwordfile         string                   EXCLUSIVE

$ cat $ORACLE_HOME/network/admin/sqlnet.ora
SQLNET.AUTHENTICATION_SERVICES=ALL

$ sqlplus sys/mypna123@userdata as sysdba

SQL*Plus: Release 10.2.0.4. - Production on Tue Sep  :: 

Copyright (c) , , Oracle.  All Rights Reserved.

ERROR:
ORA-: Authentication service failed to initialize

Enter user-name: 

$ sqlplus / as sysdba

SQL*Plus: Release 10.2.0.4. - Production on Tue Sep  :: 

Copyright (c) , , Oracle.  All Rights Reserved.

Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.4. - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

SYS@userdata>

可以看到在remote_login_passwordfile为exclusive,AUTHENTICATION_SERVICES为all的情况下本机登录只支持系统认证,不支持密码文件认证.普通用户和sys用户均不可以本地登录.但是远程登录是不受限制的.

看有哪些用户是拥有sysdba权限

SYS@userdata>grant sysdba to scott;

Grant succeeded.
SYS@userdata>select * from v$pwfile_users;

USERNAME                                 SYSDBA          SYSOPER
---------------------------------------- --------------- ---------------
SYS                                      TRUE            TRUE
SCOTT                                    TRUE            FALSE