What is the role of route preference?（）
A、It is used as a tie breaker when the same prefix is available through multiple sources
B、It is used to determine which routes to accept into the routing table
C、It is used to select the best route between multiple equal-cost paths
D、It is used to select which routing table to use for forwarding
Which directory does the Junos OS use to store syslog information by default?（）
A、A/ar/messages
B、A/ar/syslog
C、/var/tmp
D、/var/log
For security reasons， an administrator is asked to modify the system to prevent someone from leaving a terminal logged in. To enable a five minute timeout for all users， what would need to be done to accomplish this task？（）
A、Add the following line to /etc/environment： TMOUT=300
B、Add the following lines to /.profile TMOUT=5 export TMOUT
C、Execute the following command： chuser -u ALL -a TIMEOUT=5M
D、Execute the following command： chsec -u ALL -a TIMEOUT=600
（）像表一样由列组成，其查询方式与表相同，但是不包含数据。
A、同义词
B、视图
C、索引
D、过程
Referring to the exhibit, which statement is correct?（）
A、 The packets have exceeded the time-to-live value
B、 There is a loop
C、 The asterisks indicate a response time out
D、 The asterisks indicate that the traceroute is completed.
以下选项中不合法的标识符是（ ）。
A、print
B、FOR
C、&a
D、_00
