BE应为正确答案。C项的作用是指定syslog server的IP,与debug output无关,E选项可以将output指向特定的URL,请见以下输出:
R1(config)#logging host ?
Hostname or A.B.C.D IP address of the syslog server
R1#show logging | ?
append Append redirected output to URL (URLs supporting append operation
only)
begin Begin with the line that matches
exclude Exclude lines that match
include Include lines that match
redirect Redirect output to URL
section Filter a section of output
tee Copy output to URL
R1#show logging | redirect ?
flash: Uniform Resource Locator
ftp: Uniform Resource Locator
http: Uniform Resource Locator
nvram: Uniform Resource Locator
pram: Uniform Resource Locator
rcp: Uniform Resource Locator
slot0: Uniform Resource Locator
slot1: Uniform Resource Locator
tftp: Uniform Resource Locator