ntp.conf revision 289421
1193635Sedwin#
2193635Sedwin# $FreeBSD: head/etc/ntp.conf 289421 2015-10-16 14:04:16Z cy $
3193635Sedwin#
4193635Sedwin# Default NTP servers for the FreeBSD operating system.
5193635Sedwin#
6193635Sedwin# Don't forget to enable ntpd in /etc/rc.conf with:
7193635Sedwin# ntpd_enable="YES"
8193635Sedwin#
9193635Sedwin# The driftfile is by default /var/db/ntpd.drift, check
10193635Sedwin# /etc/defaults/rc.conf on how to change the location.
11193635Sedwin#
12193635Sedwin
13193635Sedwin#
14193635Sedwin# The following three servers will give you a random set of three
15193635Sedwin# NTP servers geographically close to you.
16195652Sdwmalone# See http://www.pool.ntp.org/ for details. Note, the pool encourages
17195652Sdwmalone# users with a static IP and good upstream NTP servers to add a server
18195652Sdwmalone# to the pool. See http://www.pool.ntp.org/join.html if you are interested.
19193635Sedwin#
20259973Sdelphij# The option `iburst' is used for faster initial synchronization.
21193635Sedwin#
22239464Sdelphijserver 0.freebsd.pool.ntp.org iburst
23239464Sdelphijserver 1.freebsd.pool.ntp.org iburst
24239464Sdelphijserver 2.freebsd.pool.ntp.org iburst
25239464Sdelphij#server 3.freebsd.pool.ntp.org iburst
26193635Sedwin
27193635Sedwin#
28193635Sedwin# If you want to pick yourself which country's public NTP server
29193635Sedwin# you want sync against, comment out the above servers, uncomment
30195652Sdwmalone# the next ones and replace CC with the country's abbreviation.
31193635Sedwin# Make sure that the hostnames resolve to a proper IP address!
32193635Sedwin#
33239464Sdelphij# server 0.CC.pool.ntp.org iburst
34239464Sdelphij# server 1.CC.pool.ntp.org iburst
35239464Sdelphij# server 2.CC.pool.ntp.org iburst
36193635Sedwin
37193635Sedwin#
38259973Sdelphij# Security:
39193635Sedwin#
40259973Sdelphij# By default, only allow time queries and block all other requests
41259973Sdelphij# from unauthenticated clients.
42259973Sdelphij#
43259973Sdelphij# See http://support.ntp.org/bin/view/Support/AccessRestrictions
44259973Sdelphij# for more information.
45259973Sdelphij#
46280916Sdelphijrestrict default limited kod nomodify notrap nopeer noquery
47280916Sdelphijrestrict -6 default limited kod nomodify notrap nopeer noquery
48259973Sdelphij#
49259973Sdelphij# Alternatively, the following rules would block all unauthorized access.
50259973Sdelphij#
51259973Sdelphij#restrict default ignore
52259973Sdelphij#restrict -6 default ignore
53259973Sdelphij#
54259973Sdelphij# In this case, all remote NTP time servers also need to be explicitly
55259973Sdelphij# allowed or they would not be able to exchange time information with
56259973Sdelphij# this server.
57259973Sdelphij#
58193635Sedwin# Please note that this example doesn't work for the servers in
59193635Sedwin# the pool.ntp.org domain since they return multiple A records.
60193635Sedwin#
61193635Sedwin#restrict 0.pool.ntp.org nomodify nopeer noquery notrap
62193635Sedwin#restrict 1.pool.ntp.org nomodify nopeer noquery notrap
63193635Sedwin#restrict 2.pool.ntp.org nomodify nopeer noquery notrap
64259973Sdelphij#
65259973Sdelphij# The following settings allow unrestricted access from the localhost
66259973Sdelphijrestrict 127.0.0.1
67259973Sdelphijrestrict -6 ::1
68259973Sdelphijrestrict 127.127.1.0
69193635Sedwin
70193635Sedwin#
71195652Sdwmalone# If a server loses sync with all upstream servers, NTP clients
72195652Sdwmalone# no longer follow that server. The local clock can be configured
73195652Sdwmalone# to provide a time source when this happens, but it should usually
74195652Sdwmalone# be configured on just one server on a network. For more details see
75195652Sdwmalone# http://support.ntp.org/bin/view/Support/UndisciplinedLocalClock
76195652Sdwmalone# The use of Orphan Mode may be preferable.
77193635Sedwin#
78195652Sdwmalone#server 127.127.1.0
79195652Sdwmalone#fudge 127.127.1.0 stratum 10
80289421Scy
81289421Scy# See http://support.ntp.org/bin/view/Support/ConfiguringNTP#Section_6.14.
82289421Scy# for documentation regarding leapfile. Updates to the file can be obtained
83289421Scy# from ftp://time.nist.gov/pub/ or ftp://tycho.usno.navy.mil/pub/ntp/.
84289421Scyleapfile "/etc/ntp/leap-seconds"
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