On Thu, 5 Nov 2009, David Hiers wrote:
I thought that ntp doesn't know or care about DST. It works in UTC, and the OS is responsible for any DST adjustment it wants to make.
If you're an hour (3600 seconds) off in NTP, and it takes 2000 seconds to adjust for every second you are off, it'll take 7200000 seconds to get back on track, which is about 83 days. Seems kinda long...
That's the default. You don't want NTP to change a production server from 1pm to 2pm in one giant leap. That would screw a lot of things up, especially on a VoIP server that does billing! By spreading an hour change over 83 days, it makes sure you don't totally screw up your billing. Ideally, if it were off by an hour, you'd take it out of production, update the clock, then put it back in. If you couldn't, NTP's solution is a pretty good balance. Ideally, NTP keeps your clock in sync +/- 1 second at all times, and since the OS does the translation from UTC to your server time zone, there will never be a time that it is an hour off, unless all of your time servers go down (or your network does). If we all worked on UTC and all had all of our clocks synced, we would all have a LOT easier time correlating CDRs between ourselves and our providers. That brings up another question -- do you display the start time or end time of the call? I display start time, but I'm curious if there is a standard among providers, both retail and wholesale. --------------------------------------------------------------------------- Peter Beckman Internet Guy beckman at angryox.com http://www.angryox.com/ ---------------------------------------------------------------------------