What is the command to authenticate an NTP time source? (something in those lines)
A.
#ntp authentication-key 1 md5 141411050D 7
B.
#ntp authenticate
C.
#ntp trusted-key 1
D.
#ntp trusted-key 1
Explanation:
BD
ntp authentication-key 1 md5 141411050D 7
ntp authenticate
ntp trusted-key 1
ntp update-calendar
ntp server 192.168.1.96 key 1 prefer source FastEthernet0/1
Source: Cisco Official Certification Guide, Example 11-15 Using Authentication via Keys with NTPv3, p.314
The right answer for this question is B. #ntp authenticate
R1(config)# ntp ?
access-group Control NTP access
allow Allow processing of packets
authenticate Authenticate time sources
authentication-key Authentication key for trusted time sources
there is another question that ask about:
Which IOS command is used to define the authentication KEY for NTP?
and for this the answer will be A.
A is correct:
The command “ntp authenticate” authenticates the time source.
The command “ntp authentication-key” is the authentication key for trusted time sources.