Ntpd not updating
The number represents the distance from the reference clock and is used to prevent cyclical dependencies in the hierarchy.Stratum is not always an indication of quality or reliability; it is common to find stratum 3 time sources that are higher quality than other stratum 2 time sources.These are computers that are synchronized to stratum 2 servers.
NTP uses a hierarchical, semi-layered system of time sources.
NTP can usually maintain time to within tens of milliseconds over the public Internet, and can achieve better than one millisecond accuracy in local area networks under ideal conditions.
Asymmetric routes and network congestion can cause errors of 100 ms or more.
Stratum 0 devices are also known as reference clocks.
These are computers whose system time is synchronized to within a few microseconds of their attached stratum 0 devices.