Technical data

24 FastIron Ethernet Switch Administration Guide

53-1002637-02

Network Time Protocol Version 4 (NTPv4)

When the NTP server is enabled, it will start listening on the NTP port for client requests and

responds with the reference time. Its stratum number will be the upstream time server's stratum +

1. The stratum 1 NTP server is the time server which is directly attached to the authoritative time

source.

The device cannot be configured as primary time server with stratum 1. It can be configured as

secondary time server with stratum 2 to 15 to serve the time using the local clock.

The NTP server is stateless and will not maintain any NTP client information.

System as an Authoritative NTP Server

The NTP server can operate in master mode to serve time using the local clock, when it has lost

synchronization. Serving local clock can be enabled using the master command. In this mode, the

NTP server stratum number is set to the configured stratum number. When the master command is

configured and the device was never synchronized with an upstream time server and the clock

setting is invalid, the server will respond to client's request with the stratum number set to 16.

While the device is operating in the master mode and serving the local clock as the reference time,

if synchronization with the upstream server takes place it will calibrate the local clock using the

NTP time. The stratum number will switch to that of the synchronized source +1. And when

synchronization is lost, the device switches back to local clock time with stratum number as

specified manually (or the default).

NOTE

Local time and time zone has to be configured before configuring the master command.

• The following scenarios are observed when the master command is not configured and the

NTP upstream servers are configured:

• If the synchronization with the NTP server/peer is active, the system clock is synchronized and

the reference time is the NTP time.

• If the NTP server/peer is configured but not reachable and if the local clock is valid, the server

will respond to client's request with the stratum number set to 16.

• If there is no NTP server/peer configured and if the local clock is valid, the server will respond

to client's request with the stratum number set to 16.

• If there is no NTP server/peer configured and if the local clock is invalid, the system clock is

not synchronized.

The following scenarios are observed when the master command is configured and the NTP

upstream servers are also configured:

• If the synchronization with the time server/peer is active, system clock is synchronized and the

reference time is the NTP time.If the NTP server/peer is configured but not reachable, the

system clock is synchronized. If the local time is valid then the reference time is the local clock

time.

• If the NTP server/peer is not configured, the system clock is synchronized. If the local clock is

valid, then the reference time is the local clock time.

• If the NTP server/peer is not configured and the local clock is invalid, system clock is not

synchronized.