Users Guide

Table Of Contents
Authentication
NTP authentication and the corresponding trusted key provides a reliable exchange of NTP packets with trusted time sources. NTP
authentication begins with creating the first NTP packet after the key configuration. NTP authentication uses the message digest 5
(MD5) algorithm. The key is embedded in the synchronization packet that is sent to an NTP time source.
1. Enable NTP authentication in CONFIGURATION mode.
ntp authenticate
2. Set an authentication key number and key in CONFIGURATION mode, from 1 to 4294967295.
ntp authentication-key number md5 key
The number must match in the ntp trusted-key command.
The key is an encrypted string.
3. Define a trusted key in CONFIGURATION mode, from 1 to 4294967295. This number must match the number in the ntp trusted-
key command.
ntp trusted-key number
4. Configure an NTP server in CONFIGURATION mode.
ntp server {hostname | ipv4-address | ipv6-address} [key keyid] [prefer]
hostname — Enter the keyword to see the IP address or host name of the remote device.
ipv4-address — Enter an IPv4 address in A.B.C.D format.
ipv6-address — Enter an IPv6 address in nnnn:nnnn:nnnn:nnnn:nnnn:nnnn:nnnn:nnnn format. Elision of zeros is supported.
key keyid — Enter a text string as the key exchanged between the NTP server and the client.
prefer — Enter the keyword to set this NTP server as the preferred server.
5. Configure the NTP master and enter the stratum number that identifies the NTP server hierarchy in CONFIGURATION mode, from 2
to 10. The default is 8.
ntp master {2–10}
Configure NTP
OS10(config)# ntp authenticate
OS10(config)# ntp trusted-key 345
OS10(config)# ntp authentication-key 345 mdf 0 5A60910FED211F02
OS10(config)# ntp server 1.1.1.1 key 345
OS10(config)# ntp master 7
View NTP configuration
OS10(config)# do show running-configuration
!
ntp authenticate
ntp authentication-key 345 mdf 0 5A60910FED211F02
ntp server 1.1.1.1 key 345
ntp trusted-key 345
ntp master 7
...
Sample NTP configuration
The following example shows an NTP master (11.0.0.2), server (10.0.0.1), and client (10.0.0.2) connected through a non-default VRF
instance (VRF Red). OS10 acts as an NTP server to synchronize its clock with the NTP master available in the non-default VRF instance
red and provides time to NTP clients in the VRF.
System management
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