Scenario: Synchronizing clocks with i5/OS
This scenario demonstrates how to use the i5/OS® operating system as both an SNTP server and an SNTP client to synchronize clocks in your network.
Situation
As an administrator of your company's network, maintain both your system and network clients.
Timestamps are critical to your transactions. You need to maintain synchronization in the network.
Objectives
In this scenario, YourCo,
Inc. wants to use the SNTP client on the i5/OS 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.
Details
The following figure shows the solution environment for this scenario.
Figure 1. SNTP as a client and a server
In Figure 1,
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 (systemA.yourco.com) is running i5/OS V5R3,
or later.
- System B (systemB.yourco.com) is running i5/OS V5R3,
or later.
- System B (systemB.yourco.com) 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.
- Configuring System A as an SNTP client and server
To configure the YourCo, Inc. network to use Simple Network Time Protocol (SNTP), you need to configure System A as an SNTP client and server. - Configuring your firewall to allow SNTP traffic
For this scenario, you are running a firewall on System A. To allow SNTP traffic, configure the firewall to allow the passing of UDP packets on port 123. - Configuring the SNTP client on other systems in the network
After your SNTP server runs, configure the other systems in the network to use System A as an SNTP server. For this scenario, you need to configure the SNTP client on System B. - Specifying SNTP as your time maintenance application
After you have configured the SNTP server and client, you need to verify the time adjustment (QTIMADJ) system value to ensure that Simple Network Time Protocol (SNTP) can operate as the time maintenance application on your system. - Starting SNTP manually
To enable the Simple Network Time Protocol (SNTP) application that you have configured, you need to start SNTP manually. After you change its configuration, you also need to start SNTP manually.
Parent topic:
Simple Network Time Protocol
Related concepts
SNTP client