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Cisco Intrusion Prevention System Sensor CLI Configuration Guide for IPS 7.2
OL-29168-01
Chapter 3 Setting Up the Sensor
Configuring Time
Step 6
Specify the NTP master stratum number to be assigned to the sensor. The NTP master stratum number
identifies the relative position of the server in the NTP hierarchy. You can choose a number between1
and 15. It is not important to the sensor which number yo u choose.
router(config)# ntp master stratum_number
Example
router(config)# ntp master 6
Configuring the Sensor to Use an NTP Time Source
The sensor requires a consistent time source. We recommend that you use an NTP server. Use the
following procedure to configure the sensor to use the NTP server as its time source. You can use
authenticated or unauthenticated NTP.
Note
For authenticated NTP, you must obtain the NTP server IP address, NTP server key ID, and the key value
from the NTP server.
Caution
The sensor NTP capability is designed to be compatible with Cisco routers acting as NTP servers. The
sensor may work with other NTP servers, but is not tested or supported.
To configure the sensor to use an NTP server as its time source, follow these steps:
Step 1
Log in to the CLI using an account with administrator privileges.
Step 2
Enter configuration mode.
sensor# configure terminal
Step 3
Enter service host mode.
sensor(config)# service host
Step 4
Configure unauthenticated NTP:
a.
Enter NTP configuration mode.
sensor(config-hos)# ntp-option enabled-ntp-unauthenticated
b.
Specify the NTP server IP address.
sensor(config-hos-ena)# ntp-server ip_address
c.
Verify the unauthenticated NTP settings.
sensor(config-hos-ena)# show settings
enabled-ntp-unauthenticated
-----------------------------------------------
ntp-server: 10.89.147.45
-----------------------------------------------
sensor(config-hos-ena)#