Scenario: Synchronizing clocks with IBM i

This scenario demonstrates how to use the IBM® i operating system as both an SNTP server and an SNTP client to synchronize clocks in your network.


As an administrator of your company's network, you must maintain both your system and network clients. Timestamps are critical to your transactions. You need to maintain synchronization in the network.


In this scenario, YourCo, Inc. wants to use the SNTP client on the IBM i operating system to receive time from an outside Network Time Protocol (NTP) server. To maintain the time within your network, you need to use your system as an SNTP server. In addition to configuring the SNTP client and server on your system, you need to configure your firewall to allow the SNTP client to obtain the time from an external NTP server.

The objectives of this scenario are as follows:

  • To synchronize your system with an outside NTP server.
  • To make your system function as an SNTP server for clients within your network.


The following figure shows the solution environment for this scenario.

Figure 1. SNTP as a client and a server
Diagram depicting SNTP relationships within a network

In this figure, System A functions as an SNTP client and server. As an SNTP client, System A retrieves a time value from an external time source that you specify. The SNTP application synchronizes System A's Coordinated Universal Time (UTC) with the time value from the external time source. As an SNTP server, System A sends the time value to all SNTP client systems (System B and Client A) that are connected to System A.

Prerequisites and assumptions

This scenario depends on the following prerequisites and assumptions:

  • System A ( is running IBM i V5R3, or later.
  • System B ( is running IBM i V5R3, or later.
  • System B ( and Client A are running SNTP clients.
  • You have a time management strategy.
  • You have already set the time zone system value.
  • You want to use SNTP as the time-maintenance application on your system.

Configuration steps

To configure the YourCo, Inc. network to use SNTP, complete the following tasks.