How to Configure Network Time Protocol on NetScaler

This article describes how to configure Network Time Protocol (NTP) on NetScaler.

You can configure NTP by modifying the ntp.conf file in FreeBSD when using NetScaler.

Configure NTP on NetScaler Using Command Line Interface

To configure NTP from the command line interface, run the following command:
add ntp server (<serverIP> | <serverName>) [-minpoll <positive_integer>][-maxpoll <positive_integer>]

For example, add ntp server 10.217.146.8 -minpoll 6 -maxpoll 10

where,
Server is the name or IP address of the NTP server.
Minpoll is the minimum number of seconds after which NTP server must poll NTP messages.
Maxpoll is the maximum number of seconds after which NTP server must poll NTP messages.

To verify the configuration in the shell prompt, run the following command:
cd /nsconfig
root@ReproNS-07# cat ntp.conf
server 10.217.146.8 minpoll 6 maxpoll 10

To configure the NTP parameters, run the following command:
set ntp param [-authentication ( YES | NO )] [-trustedkey <positive_integer> ...] [-autokeyLogsec <positive_integer>] [-revokeLogsec <positive_integer>]
unset ntp param
show ntp param

Refer to Citrix Documentation for all operations that can be performed on "ntp server".

Configure NTP on NetScaler Using Configuration Utility

To configure NTP from configuration utility, complete the following steps:

1. Expand the System node in the configuration utility.

2. Select NTP Servers.

3. Click Add.

4. Type the information about the NTP server in the Create NTP Server dialog box.

5. Click NTP Synchronization to enable synchronization.

   

For more information refer to Citrix Documentation - Configuring Clock Synchronization on NetScaler.

Additional Features From NetScaler Software Release 9.3 Onwards

Starting with NetScaler software release 9.3, you can select a particular NTP server as the preferred NTP server.

When you select this option, the appliance synchronizes with that particular server first. This option is applicable if you have configured more than one NTP server.

Additional Features in the NetScaler Software Release 10 Onwards

Starting with NetScaler 10 the following NTP parameter are featured:

• Key Identifier: You must add the key identifier to the list of Trusted Key IDs in the Authentication Parameters.
  Minimum value: 1
  Maximum value: 65534.
  Note: Do not add the key identifier if you select the Auto Key option.

• Auto Key: Use the Autokey protocol for the specified server.

  

• Authentication: Enables NTP authentication.

  Possible values: YES, NO.
  Default: YES.

• Trusted Key IDs: The trusted key IDs. While adding an NTP server, you select a key identifier from this list.

  Minimum value: 1
  Maximum value: 65534.

• Revoke Interval: The interval between re-randomization of certain cryptographic values used by the Autokey protocol, as a power of 2, in seconds.

  Default value: 17 (2^17=36 hours).

• Automax Interval: The interval between regeneration of the session key list used with the Autokey protocol, as a power of 2, in seconds.

  Default value: 12 (2^12=1.1 hours).

  

When you add an NTP server from the NetScaler appliance, the NTP configuration does not appear in the ns.conf file. Instead, the NTP server information is recorded in the ntp.conf file. The ntp.conf file is located in the /nsconfig directory.

Note: If you have configured the NetScaler appliances in a high availability setup, the NTP configuration does not synchronize between the primary and the secondary appliances. You must configure NTP individually on each appliance.

The commands related to NTP synchronization are as follows.

To enable NTP synchronization:
enable ntp sync
To disable NTP synchronization:
disable ntp sync

Any errors in NTP synchronization is logged in ntpd.log file in the /var/log directory.