Aruba Networks PowerConnect W Clearpass 100 Software Deployment Manual page 322

To ensure that authentication, authorization, and accounting (AAA) is performed correctly, it is vital that
the server maintains the correct time of day at all times. It is strongly recommended that you configure one
or more NTP servers to automatically synchronize the server's time.
NTP can interfere with timekeeping in virtual machines. The default virtual machine configuration will
automatically synchronize its time with the host server, and so you should not configure NTP if you are
using virtualization for the Amigopod Visitor Management Appliance. However, make sure that the host is
configured to keep its clock in sync with a suitable time source.
If one is available, it is strongly recommended that you use an NTP server that is available on your local
network. This will improve timekeeping and will eliminate the need for additional Internet traffic for the
time server.
To use a public NTP server, enter the following hostnames:
0.pool.ntp.org
1.pool.ntp.org
2.pool.ntp.org
You can also use NTP pool servers located in your region. For more information, refer to the NTP Pool
Project Web
Select the Set server's clock using NTP server check box to perform a single clock synchronization with
the specified time servers. The synchronization will take place when you click the Save Changes button.
You should provide a local NTP server. Do not use the default setting as this may be unreliable.
To set the server's time manually, enter a value in the Server Time field using the recommended format, or
click the ... button to display a date/time chooser.
Click the Save Changes button to apply the new time and date settings.
If the server's clock is running slow, changing the server's time may cause your current login to expire. In this case
you will need to log in again after clicking the Save Changes button.
322 | Administrator Tasks
site: http://www.pool.ntp.org.
Amigopod 3.7 | Deployment Guide