Configuring Ntp Authentication - Cisco Nexus 7000 Series Configuration Manual

Configuring NTP Authentication

Configuring NTP Authentication
You can configure the device to authenticate the time sources to which the local clock is synchronized. When
you enable NTP authentication, the device synchronizes to a time source only if the source carries one of the
authentication keys specified by the ntp trusted-key command. The device drops any packets that fail the
authentication check and prevents them from updating the local clock. NTP authentication is disabled by
default.
Before You Begin
Authentication for NTP servers and NTP peers is configured on a per-association basis using the key keyword
on each ntp server and ntp peer command. Make sure that you configured all NTP server and peer associations
with the authentication keys that you plan to specify. Any ntp server or ntp peer commands that do not
specify the key keyword will continue to operate without authentication.
Procedure
Step 1
Step 2
Step 3
Step 4
Cisco Nexus 7000 Series NX-OS System Management Configuration Guide
54
Command or Action
configure terminal
Example:
switch# configure terminal
switch(config)#
[no] ntp authentication-key number md5
md5-string
Example:
switch(config)# ntp authentication-key 42
md5 aNiceKey
show ntp authentication-keys
Example:
switch(config)# show ntp
authentication-keys
[no] ntp trusted-key number
Example:
switch# config t
Enter configuration commands, one per line.
End with CNTL/Z.
switch(config)# ntp authentication-key 42
Purpose
Enters global configuration mode.
Defines the authentication keys. The device
does not synchronize to a time source unless
the source has one of these authentication keys
and the key number is specified by the ntp
trusted-key number command.
The range for authentication keys is from 1 to
65535. For the MD5 string, you can enter up to
eight alphanumeric characters.
Beginning with Cisco NX-OS Release
7.3(0)D1(1), you can enter up to 32
alphanumeric characters for the MD5 string.
(Optional)
Displays the configured NTP authentication
keys.
Specifies one or more keys (defined in Step 2)
that a time source must provide in its NTP
packets in order for the device to synchronize
to it. The range for trusted keys is from 1 to
65535.
Configuring NTP