I am looking at using NTP statistics as a quick measure of latency in our WAN, but can't make sense of the numbers. For example, I have a router on the same LAN as its NTP peer and 'sh ntp associations' gives this:
address ref clock st when poll reach delay offset disp
+~10.68.50.6 128.252.19.1 2 54 1024 377 1.8 -0.21 0.2
*~10.68.50.5 128.252.19.1 2 466 1024 377 1.9 0.15 0.1
* master (synced), # master (unsynced), + selected, - candidate, ~ configured
My questions are:
1. Is there really 1.8 and 1.9 seconds of delay between these peers?
2. If so, how does that square with ping response times in the 1-4 msec range?
3. Why does a query of the SNMP MIB show 0.127 and 0.116 seconds of delay (MIB var: .1.3.6.1.4.1.9.9.168.1.2.1.1.24 queried using Getif)?
4. Is NTP peer delay a reasonable way to measure network latency or am I barking up the wrong tree?
Thanks in advance.
Bob