The Network Time Protocol (NTP) server provides the correct network time on your device. NTP is used to synchronize the time on devices across a network.
The Network Time Protocol server is used to obtain the correct time from an external time source and adjust the local time in each connected device. When NTP server functionality is enabled, the NTP server starts listening on the NTP port for client requests and responds with the reference time. Up to eight server addresses can be configured in IPv4 or IPv6 format. When multiple NTP server addresses are configured, the NTP algorithm finds the most reliable server and uses this as the active NTP server. If there are no reachable time servers, then the local device time becomes the default time until a new active time server is configured. If an NTP server loses synchronization, it will operate in master mode to serve time using the local clock. Use the ntp master command to enable the serving of local time.
The NTP server is stateless and does not maintain NTP client information. Network time synchronization is guaranteed only when a common external time server is used by all devices.
Important
Although time-stepping corrects a large offset after a reload, as a best practice do not manually change the time after NTP synchronization.