1 1.7 fredb # $NetBSD: ntp.conf,v 1.7 2003/12/07 16:02:35 fredb Exp $ 2 1.1 fair # 3 1.7 fredb # NetBSD default Network Time Protocol (NTP) configuration file for ntpd 4 1.1 fair 5 1.1 fair # Process ID file, so that the daemon can be signalled from scripts 6 1.1 fair 7 1.3 lukem pidfile /var/run/ntpd.pid 8 1.1 fair 9 1.2 simonb # The correction calculated by ntpd(8) for the local system clock's 10 1.7 fredb # drift is stored here. 11 1.1 fair 12 1.3 lukem driftfile /var/db/ntp.drift 13 1.1 fair 14 1.7 fredb # Suppress the syslog(3) message for each peer synchronization change. 15 1.1 fair 16 1.3 lukem logconfig -syncstatus 17 1.5 fredb 18 1.5 fredb # This will help minimize disruptions due to network congestion. Don't 19 1.5 fredb # do this if you configure only one server! 20 1.5 fredb 21 1.5 fredb tos minsane 2 22 1.1 fair 23 1.7 fredb # Hereafter should be "server" or "peer" statements to configure other 24 1.7 fredb # hosts to exchange NTP packets with. Peers should be selected in such 25 1.7 fredb # a way that the network path to them is symmetric (that is, the series 26 1.7 fredb # of links and routers used to get to the peer is the same one that the 27 1.7 fredb # peer uses to get back. NTP assumes such symmetry in its network delay 28 1.7 fredb # calculation. NTP will apply an incorrect adjustment to timestamps 29 1.7 fredb # received from the peer if the path is not symmetric. This can result 30 1.7 fredb # in clock skew (your system clock being maintained consistently wrong 31 1.7 fredb # by a certain amount). 32 1.7 fredb # 33 1.1 fair # The best way to select symmetric peers is to make sure that the 34 1.7 fredb # network path to them is as short as possible (this reduces the chance 35 1.7 fredb # that there is more than one network path between you and your peer). 36 1.7 fredb # You can measure these distances with the traceroute(8) program. The 37 1.7 fredb # best place to start looking for NTP peers for your system is within 38 1.7 fredb # your own network, or at your Internet Service Provider (ISP). 39 1.1 fair # 40 1.7 fredb # Ideally, you should select at least three other systems to talk NTP 41 1.7 fredb # with, for an "what I tell you three times is true" effect. 42 1.1 fair # 43 1.1 fair 44 1.3 lukem #peer an.ntp.peer.goes.here 45 1.3 lukem #server an.ntp.server.goes.here 46 1.4 agc 47 1.6 fredb # Public servers from the pool.ntp.org project. Volunteer's servers 48 1.6 fredb # are dynamically assigned to the CNAMES below via DNS round-robin. 49 1.6 fredb # The pool.ntp.org project needs more volunteers! The only criteria to 50 1.6 fredb # join are a nailed-up connection and a static IP address. For details, 51 1.6 fredb # see the web page: 52 1.6 fredb # 53 1.4 agc # http://www.pool.ntp.org/ 54 1.6 fredb # 55 1.6 fredb 56 1.6 fredb # The country codes can help you find servers that are net-wise close. 57 1.6 fredb # As explained above, closer is better... 58 1.4 agc 59 1.6 fredb # Northern U.S.A 60 1.6 fredb #server ca.pool.ntp.org 61 1.6 fredb #server us.pool.ntp.org 62 1.6 fredb #server us.pool.ntp.org 63 1.6 fredb 64 1.6 fredb # Northern Europe 65 1.6 fredb #server de.pool.ntp.org 66 1.6 fredb #server de.pool.ntp.org 67 1.6 fredb #server dk.pool.ntp.org 68 1.6 fredb 69 1.6 fredb # Depending on the vagaries of DNS can occasionally pull in the same 70 1.6 fredb # server twice. The following CNAMES are guaranteed to be disjoint, at 71 1.6 fredb # least over some short interval. 72 1.6 fredb 73 1.6 fredb server 0.pool.ntp.org 74 1.6 fredb server 1.pool.ntp.org 75 1.6 fredb server 2.pool.ntp.org 76