Ntp not updating system clock
The cost is a little processing power and memory, but for a modern server this is negligible. Approved by Ubuntu Technical Board # on 2011-02-08 (LP: #104525). server 0.server 1.server 2.server 3.remote refid st t when poll reach delay offset jitter ============================================================================== stratum2-2. 1.70 2 u 5 64 377 68.461 -44.274 110.334 ntp2.m-online.n 126.96.36.199 2 u 5 64 377 54.629 -27.318 78.882 *145.2 .
Later on anytime a new interface comes up it retries to update the time - while doing so it will try to slowly drift time as long as the delta it has to cover isn't too big.
Stratum 2 servers then get their time from the stratum 1 servers, while stratum 3 servers synchronize with stratum 2 sources.
Essentially stratum n 1 will synchronize against stratum n, the highest limit is 15, while 16 refers to a device that is not synchronized.
Note: These examples are based on the Cent OS 7 operating system so steps may vary slightly for other Linux distributions.
In this version chronyd is installed by default, however we will still cover the older ntpd for completeness as this is still widely used.