Linux系统中的帐号文件是()。
A、/etc/passwd
B、/etc/shadow
C、/etc/password
D、/etc/gshadow
半双工操作是指电路的一端用(),另一端用双工操作的一种工作方式。
View the Exhibit and examine the attributes of an undo tablespace. In an OLTP system, the user SCOTT hasstarted a query on a large table in the peak transactional hour that performs bulk inserts. The query runs formore than 15 minutes and then SCOTT receives the following error:ORA-01555: snapshot too old What could be the reason for this error()
A、 The query is unable to get a read-consistent image.
B、 There is not enough space in Flash Recovery Area.
C、 There is not enough free space in the flashback archive.
D、 The query is unable to place data blocks in undo tablespace
下列攻击手段中,基于网络的入侵防护系统无法阻断的是( )。
A、SYNFlooding
B、SQL注入
C、DDOS
D、PingofDeath
LEAP认证过程中,AP仅仅担任()的角色。
A、屏蔽网络流量
B、转发通道
C、质询信息
D、反向认证
请叙述蓄电池组容量测试必须遵循的基本原则。