单选题The man page for command shows the following syntax: The man page for command shows the following syntax: command [ -a | -b ] Which of the following statements is true regarding this entry?（）A Either the -a or flag -b may be used, but not both.B If the

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第2题：

Which of the following conclusions is most appropriate to draw to describe why du shows fewer blocks used than df?（）

• A、 The df command only counts the number of disk blocks and superblocks. 
• B、 The df command ignores space used for inodes, gnodes, and vnodes.
• C、 The du command does not take into account filesystem metadata. 
• D、 The du command counts indirect blocks and superblocks in its calculations. 

第3题：

Which of the following statements is TRUE concerning the po column of the vmstat command？（）

• A、 The sys is high when po is high.
• B、 The po represents the number of page steals.
• C、 The low values usually indicate insufficient paging space.
• D、 The low values usually indicate sufficient memory for the load.

第4题：

The command frame-relay map ip 10.121.16.8 102 broadcast was entered on the router. Which of the following statements is true concerning this command（）。

• A、This command should be executed from the global configuration mode
• B、The IP address 10.121.16.8 is the local router port used to forward data
• C、102 is the remote DLCI that will receive the information
• D、This command is required for all Frame Relay configurations
• E、The broadcast option allows packets, such as RIP updates, to be forwarded across the PVC

第5题：

Which of the following has NO effect on controlling the access permissions needed to run the "date" command on the remote machine "Earth" using the following syntax？rsh Earth date（）。

• A、The local file： /etc/.netrc
• B、The remote file： ~/ .rhosts
• C、The securetcpip command
• D、The remote file： /etc/hosts.equiv

第6题：

You are managing an Oracle Database 11g instance with ASM storage. The ASM instance is down. To know the details of the disks in the DATA disk group , you issued the following ASMCMD command: ASMCMD> lsdsk -I -d DATA Which statement is true regarding the outcome of this command?（）

• A、The command succeeds but it retrieves only the disk names.
• B、The command produces an error because the ASM instance is down.
• C、The command succeeds but it shows only the status of the ASM instance.
• D、The command succeeds and retrieves information by scanning the disk headers based on an ASM_DISKSTRING value.

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第13题：

Which of the following statements are true concerning the command ip sla monitor responder typetcpconnect ipaddress 10.1.1.1 port 23？（Choose all that apply.）（）

• A、The command will initiate a probe with a destination IP address of 10.1.1.1
• B、The command is used on the IP SLA responder and the IP SLA source
• C、The command will allow only source address 10.1.1.1 to source probes
• D、The command will initiate a probe with a destination Telnet port
• E、The command is used to make the router a responder
• F、The command will initiate a probe with a source port of 23

第14题：

Your database is up and running and one of your three control files is accidentally erased. You start RMAN and run the following command：   RESTORE CONTROLFILE FROM AUTOBACKUP；   Which of the following statements is true？（） 

• A、 The command restores only the missing control file.
• B、 The command restores all the control files.
• C、 The command fails because the database is running.
• D、 This is the correct way to address this problem.
• E、 This is not the correct way to address this problem.

第15题：

The following configuration command was entered into a router:ip route 172.16.3.0 255.255.255.0 192.168.2.4 Which of the following statements are true regarding this configuration change?（）

• A、The default administrative distance is used.
• B、The command is used to establish a static route.
• C、The command is used to configure the router interfaces.
• D、The command is used to establish a stub network.
• E、The subnet mask for the source address is 255.255.255.0

第16题：

An administrator attempts to open a web page and sees the following error: 'Error 404: Page not found'. The administrator then uses the ping command and finds that the default gateway cannot be pinged. At which of the following layers does the problem MOST likely reside?（）

• A、Layer 1
• B、Layer 4
• C、Layer 5
• D、Layer 7

第17题：

The man page for command shows the following syntax: The man page for command shows the following syntax: command [ -a | -b ] Which of the following statements is true regarding this entry?（）

• A、Either the -a or flag -b may be used, but not both.
• B、If the flag -a is used then the flag -b also must be used.
• C、One of the -a or -b flags must be used, but not both at the same time.
• D、Both the flags may be used together, but neither are mandatory.

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