This topic provides information about the SNTP client on i5/OS™.
When SNTP is configured as a client, the iSeries™ server retrieves a time value from an external time source. You can specify from which sources (up to three) to retrieve the time value. This external time value is compared to the iSeries system time. If the iSeries time value does not match the external time source, a time adjustment begins. The iSeries system time is adjusted until the required time value is reached.
The SNTP client allows you to configure the i5/OS operating system to poll a Network Time Protocol (NTP) or SNTP server to find out the time. The SNTP client updates the system clock. Most applications use the system clock as their time source. By updating the system clock, applications reflect the synchronized time obtained from the time server.
The first server in the list that can provide valid time service will be selected. When the selected time server fails, a new time server will be selected. The time server should be selected based on minimum network response time delay at the location where the iSeries server is installed.
A list of public time servers is maintained on the Internet. To locate a time server, you can use a search engine with a query of NTP servers.
You can run the SNTP client and the SNTP server concurrently on your iSeries server. This allows you to obtain time from an outside source, and then serve that time to clients on your network. To do this, you need to synchronize the clocks on your network.