Default Setting
Feature
No access control is specified.
NTP access restrictions
The source address is set by the outgoing interface.
NTP packet source IP address
NTP is enabled on all interfaces by default. All interfaces receive NTP packets.
Configuring NTP Authentication
To configure NTP authentication, perform this procedure:
SUMMARY STEPS
1.
enable
2.
configure terminal
3.
[
no
]
ntp authenticate
4.
[
no
]
ntp authentication-key number
{
md5
|
cmac-aes-128
|
hmac-sha1
|
hmac-sha2-256
}
value
5.
[
no
]
ntp trusted-key key-number
6.
[
no
]
ntp server ip-address key key-id
[
prefer
]
7.
end
DETAILED STEPS
Purpose
Command or Action
Enables privileged EXEC mode.
enable
Step 1
Example:
Enter your password if prompted.
Device>
enable
Enters global configuration mode.
configure terminal
Example:
Step 2
Device#
configure terminal
Enables NTP authentication.
[
no
]
ntp authenticate
Step 3
Example:
Use the
no
form of this command to disable NTP
authentication
Device(config)#
ntp authenticate
Defines the authentication keys.
[
no
]
ntp authentication-key number
{
md5
|
cmac-aes-128
|
hmac-sha1
|
hmac-sha2-256
}
value
Step 4
• Each key has a key number, a type, and a value.
Example:
• Keys can be one of the following types:
Device(config)#
ntp authentication-key 42 md5
•
md5
: Authentication using the MD5 algorithm.
aNiceKey
System Management Configuration Guide, Cisco IOS XE Fuji 16.8.x (Catalyst 9500 Switches)
15
Administering the Device
Configuring NTP Authentication
