In an NTP architecture, the NTP client changes the time to reflect that of the chosen NTP server. The NTP server will not change its time to match that of a clients.
NTP peers can act as clients and servers to each other – they blend their time to each other. An NTP peer will shift its click to synchronise with a peer, at a maximum of two minutes per query.
NTP peers are configured as
ntp peer x.x.x.x in global configuration mode. Replace x.x.x.x with the IP address of the peer.