1193635Sedwin#
2193635Sedwin# $FreeBSD: stable/10/etc/ntp.conf 335950 2018-07-04 14:10:36Z ian $
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#
14316121Scy# Set the target and limit for adding servers configured via pool statements
15316121Scy# or discovered dynamically via mechanisms such as broadcast and manycast.
16316121Scy# Ntpd automatically adds maxclock-1 servers from configured pools, and may
17316121Scy# add as many as maxclock*2 if necessary to ensure that at least minclock 
18316121Scy# servers are providing good consistant time.
19316121Scy#
20316121Scytos minclock 3 maxclock 6
21316121Scy
22316121Scy#
23316121Scy# The following pool statement will give you a random set of NTP servers
24316121Scy# geographically close to you.  A single pool statement adds multiple
25316121Scy# servers from the pool, according to the tos minclock/maxclock targets.
26316121Scy# See http://www.pool.ntp.org/ for details.  Note, pool.ntp.org encourages
27195652Sdwmalone# users with a static IP and good upstream NTP servers to add a server
28195652Sdwmalone# to the pool. See http://www.pool.ntp.org/join.html if you are interested.
29193635Sedwin#
30259974Sdelphij# The option `iburst' is used for faster initial synchronization.
31193635Sedwin#
32316121Scypool 0.freebsd.pool.ntp.org iburst
33193635Sedwin
34193635Sedwin#
35193635Sedwin# If you want to pick yourself which country's public NTP server
36316121Scy# you want to sync against, comment out the above pool, uncomment
37316121Scy# the next one, and replace CC with the country's abbreviation.
38316121Scy# Make sure that the hostname resolves to a proper IP address!
39193635Sedwin#
40316121Scy# pool 0.CC.pool.ntp.org iburst
41193635Sedwin
42193635Sedwin#
43316121Scy# To configure a specific server, such as an organization-wide local
44316121Scy# server, add lines similar to the following.  One or more specific
45316121Scy# servers can be configured in addition to, or instead of, any server
46316121Scy# pools specified above.  When both are configured, ntpd first adds all
47316121Scy# the specific servers, then adds servers from the pool until the tos
48316121Scy# minclock/maxclock targets are met.
49316121Scy#
50316121Scy#server time.my-internal.org iburst
51316121Scy
52316121Scy#
53259974Sdelphij# Security:
54193635Sedwin#
55259974Sdelphij# By default, only allow time queries and block all other requests
56259974Sdelphij# from unauthenticated clients.
57259974Sdelphij#
58316121Scy# The "restrict source" line allows peers to be mobilized when added by
59316121Scy# ntpd from a pool, but does not enable mobilizing a new peer association
60316121Scy# by other dynamic means (broadcast, manycast, ntpq commands, etc).
61316121Scy#
62259974Sdelphij# See http://support.ntp.org/bin/view/Support/AccessRestrictions
63259974Sdelphij# for more information.
64259974Sdelphij#
65335950Sianrestrict default limited kod nomodify notrap noquery nopeer
66335950Sianrestrict source  limited kod nomodify notrap noquery
67316121Scy
68259974Sdelphij#
69259974Sdelphij# Alternatively, the following rules would block all unauthorized access.
70259974Sdelphij#
71259974Sdelphij#restrict default ignore
72259974Sdelphij#
73259974Sdelphij# In this case, all remote NTP time servers also need to be explicitly
74259974Sdelphij# allowed or they would not be able to exchange time information with
75259974Sdelphij# this server.
76259974Sdelphij#
77193635Sedwin# Please note that this example doesn't work for the servers in
78193635Sedwin# the pool.ntp.org domain since they return multiple A records.
79193635Sedwin#
80193635Sedwin#restrict 0.pool.ntp.org nomodify nopeer noquery notrap
81193635Sedwin#restrict 1.pool.ntp.org nomodify nopeer noquery notrap
82193635Sedwin#restrict 2.pool.ntp.org nomodify nopeer noquery notrap
83259974Sdelphij#
84259974Sdelphij# The following settings allow unrestricted access from the localhost
85259974Sdelphijrestrict 127.0.0.1
86335950Sianrestrict ::1
87193635Sedwin
88193635Sedwin#
89195652Sdwmalone# If a server loses sync with all upstream servers, NTP clients
90195652Sdwmalone# no longer follow that server. The local clock can be configured
91195652Sdwmalone# to provide a time source when this happens, but it should usually
92195652Sdwmalone# be configured on just one server on a network. For more details see
93195652Sdwmalone# http://support.ntp.org/bin/view/Support/UndisciplinedLocalClock
94195652Sdwmalone# The use of Orphan Mode may be preferable.
95193635Sedwin#
96195652Sdwmalone#server 127.127.1.0
97195652Sdwmalone#fudge 127.127.1.0 stratum 10
98295461Scy
99295461Scy# See http://support.ntp.org/bin/view/Support/ConfiguringNTP#Section_6.14.
100295461Scy# for documentation regarding leapfile. Updates to the file can be obtained
101295461Scy# from ftp://time.nist.gov/pub/ or ftp://tycho.usno.navy.mil/pub/ntp/.
102335950Sian# Use either leapfile in /etc/ntp or periodically updated leapfile in /var/db.
103295461Scy#leapfile "/etc/ntp/leap-seconds"
104295461Scyleapfile "/var/db/ntpd.leap-seconds.list"
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