Configuring Ntp Access Restrictions - Cisco Nexus 7000 Series Configuration Manual

Configuring NTP
Step 5
Step 6
Step 7
Step 8

Configuring NTP Access Restrictions

You can control access to NTP services by using access groups. Specifically, you can specify the types of
requests that the device allows and the servers from which it accepts responses.
If you do not configure any access groups, NTP access is granted to all devices. If you configure any access
groups, NTP access is granted only to the remote device whose source IP address passes the access list criteria.
Procedure
Step 1
Step 2
Command or Action
md5 aNiceKey
switch(config)# ntp server 10.1.1.1 key 42
switch(config)# ntp trusted-key 42
switch(config)# ntp authenticate
switch(config)# copy running-config
startup-config
[########################################]
100%
switch(config)#
show ntp trusted-keys
Example:
switch(config)# show ntp trusted-keys
[no] ntp authenticate
Example:
switch(config)# ntp authenticate
show ntp authentication-status
Example:
switch(config)# show ntp
authentication-status
copy running-config startup-config
Example:
switch(config)# copy running-config
startup-config
Command or Action
configure terminal
Example:
switch# configure terminal
switch(config)#
[no] ntp access-group {peer | serve
| serve-only | query-only}
access-list-name
Cisco Nexus 7000 Series NX-OS System Management Configuration Guide
Configuring NTP Access Restrictions
Purpose
This command provides protection against
accidentally synchronizing the device to a time
source that is not trusted.
(Optional)
Displays the configured NTP trusted keys.
Enables or disables the NTP authentication
feature. NTP authentication is disabled by
default.
(Optional)
Displays the status of NTP authentication.
(Optional)
Copies the running configuration to the startup
configuration.
Purpose
Enters global configuration mode.
Creates or removes an access group to control NTP access
and applies a basic IP access list.
55