On Wed, 3 Apr 2024 at 09:26, Sameera Unnisa <shaiksameer.sa...@gmail.com> wrote:
> I have my ntp.conf as below > > "pool -4 server1 true minpoll 6 maxpoll 10 iburst" > "pool -6 server1 true minpoll 6 maxpoll 10 iburst" > > I could see after 3rd request the very next 4th request is happening > earlier than minpoll interval i.e 2^6 sec. > I see two distinct issues that may explain what you're seeing, but note it's not entirely clear what you're seeing. You don't mention how you're seeing the requests. Are you looking at a packet capture? Does the early request occur on both IPv4 and IPv6? 1. The "pool" directive, as opposed to "server", instructs ntpd to attempt to spin up as many associations for each hostname as possible, up until ntpd has maxclock associations. With the above two lines being the entirety of ntp.conf, I'd expect "tos maxclock 10" to be the default. If server1 resolves to more than one A (IPv4) or AAAA (IPv6) record, ntpd will solicit each in turn until 8 more associations are started. The "POOL" associations, as seen in `ntpq -p` output, count for 2 of the 10. At the risk of wandering into the weeds a bit, the initial solicitation request appears just like a normal NTP client request, but the response is not processed for time. Instead, it results in starting an association with the responding IP address and scheduling the next solicitation, if any. 2. "iburst" instructs ntpd to initially send a sequence of 6 requests at least 2 seconds apart, assuming a response is received for each, to speed initial synchronization. If the association has become unreachable for some time, iburst is activated again when responses are once again received. Wandering in weeds again, stay away from "burst", which is intended for synchronization occurring over an intermittent connection, such over a dialup modem connection, where very high minpoll is used to keep down costs by polling as infrequently as every 36 hours. It causes the burst behavior on every query, rather than only initially. If you continue to have problems, consider providing the output of `ntpq -crv -w -clpeers` redacted of any names or addresses you wish. Cheers, Dave Hart
