Dear Jochen, You extracted description is right , we are at stratum 2 and just syncing its time with stratum 1 level GPS device.
Litte bit confused with your conclusion. When leap second will happen on GPS what will the impact on our stratum 2 level server and below beyond ( Straum 3 client etc ) Regards, kashif -----Original Message----- From: Jochen Bern [mailto:jochen.b...@linworks.de] Sent: Wednesday, June 10, 2015 6:43 PM To: Kashif Mumtaz Tahir Cc: questions@lists.ntp.org Subject: Re: Re: [ntp:questions] Leap Second on NTP server at stratum 2 On 06/10/2015 01:27 PM, Kashif Mumtaz Tahir wrote: > Dear Macro, > We just want to sync seamless with leap seconds. [...] > Should we need to change/tune anything. I read your description as: -- There is a GPS device that actually *speaks NTP* (as opposed to, e.g., being connected to a server with a serial cable) -- This device feeds a central stratum 2 server running ntpd -- Everything else of interest is an NTP (not SNTP) client of that central server -- No special configs beyond the above, in particular, -- no additional external NTP servers, -- no leap seconds file, and -- no suppression of stepping configured on any of the machines. My conclusions: -- Whatever announcement the GPS unit makes of the upcoming leap second will be forwarded to the various machines. -- You hopefully have historic records, vendor statements, or whatever indicating that this GPS unit *will* announce a leap second to be *inserted*. (It mistakenly announcing a *negative* leap should be highly improbable, but I have no idea how likely it is to find a GPS unit that flat out doesn't propagate leap second announcements.) -- The job of actually "executing" the leap second will be left to the OS kernel of every individual machine - if you cannot afford them hitting a historic or new bug that night, you should start testing kernel versions with simulated leap seconds ASAP. -- There is a (very small) chance that in the leap second night, your single-point-of-failure GPS unit will somehow cease to work before any announcement happens and your platform will never learn of the upcoming leap second - in which case you'll find it working but being offset by one second in the morning. Regards, J. Bern -- *NEU* - NEC IT-Infrastruktur-Produkte im <http://www.linworks-shop.de/>: Server--Storage--Virtualisierung--Management SW--Passion for Performance Jochen Bern, Systemingenieur --- LINworks GmbH <http://www.LINworks.de/> Postfach 100121, 64201 Darmstadt | Robert-Koch-Str. 9, 64331 Weiterstadt PGP (1024D/4096g) FP = D18B 41B1 16C0 11BA 7F8C DCF7 E1D5 FAF4 444E 1C27 Tel. +49 6151 9067-231, Zentr. -0, Fax -299 - Amtsg. Darmstadt HRB 85202 Unternehmenssitz Weiterstadt, Geschäftsführer Metin Dogan, Oliver Michel _______________________________________________ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions