OCP-1Z0-053-V12.02-51题

51.To control the execution of a server process when it is receiving bad packets from a potentially

malicious client, you set the SEC_PROTOCOL_ERROR_FURTHER_ACTION initialization parameter as

follows:

SQL> ALTER SYSTEM SET SEC_PROTOCOL_ERROR_FURTHER_ACTION = Drop,10;

What is the significance of this setting?

A. It terminates the client connection after 10 bad packets and the client cannot reconnect to the same

instance.

B. It terminates the client connection after 10 bad packets but the client can still reconnect, and attempt

the same operation again.

C. It terminates the client connection 10 seconds after receiving a bad packet and the client cannot

reconnect to the same instance.

D. It terminates the client connection after receiving a bad packet and the client can reconnect to the

same instance after 10 minutes.

Answer: B

答案解析：

参考：http://docs.oracle.com/cd/E11882_01/server.112/e40402/initparams227.htm#REFRN10282

B,在发现有10个坏包后终止客户端连接，但客户端仍然可以重新连接，并再次尝试同样的操作。

SEC_PROTOCOL_ERROR_FURTHER_ACTION specifies the further execution of a server process when receiving bad packets from a possibly malicious client.

Values:

• CONTINUE

  The server process continues execution. The database server may be subject to a Denial of Service (DoS) if bad packets continue to be sent by a malicious client.

• (DELAY,integer)

  The client experiences a delay of integer seconds before the server process accepts the next request from the same client connection. Malicious clients are prevented from excessive consumption of server resources while legitimate clients experience a degradation in performance but can continue to function.

• (DROP,integer)

  The server forcefully terminates the client connection after integer cumulative bad packets. The server protects itself at the expense of the client (for example, a client transaction may be lost). The client may reconnect and attempt the same operation.