xref: /freebsd/usr.sbin/ntp/ntpd/ntp.conf (revision 7ec2f6bce5d28e6662c29e63f6ab6b7ef57d98b2)
1#
2# $FreeBSD$
3#
4# Default NTP servers for the FreeBSD operating system.
5#
6# Don't forget to enable ntpd in /etc/rc.conf with:
7# ntpd_enable="YES"
8#
9# The driftfile is by default /var/db/ntpd.drift, check
10# /etc/defaults/rc.conf on how to change the location.
11#
12
13#
14# Set the target and limit for adding servers configured via pool statements
15# or discovered dynamically via mechanisms such as broadcast and manycast.
16# Ntpd automatically adds maxclock-1 servers from configured pools, and may
17# add as many as maxclock*2 if necessary to ensure that at least minclock
18# servers are providing good consistent time.
19#
20tos minclock 3 maxclock 6
21
22#
23# The following pool statement will give you a random set of NTP servers
24# geographically close to you.  A single pool statement adds multiple
25# servers from the pool, according to the tos minclock/maxclock targets.
26# See http://www.pool.ntp.org/ for details.  Note, pool.ntp.org encourages
27# users with a static IP and good upstream NTP servers to add a server
28# to the pool. See http://www.pool.ntp.org/join.html if you are interested.
29#
30# The option `iburst' is used for faster initial synchronization.
31#
32pool 0.freebsd.pool.ntp.org iburst
33
34#
35# If you want to pick yourself which country's public NTP server
36# you want to sync against, comment out the above pool, uncomment
37# the next one, and replace CC with the country's abbreviation.
38# Make sure that the hostname resolves to a proper IP address!
39#
40# pool 0.CC.pool.ntp.org iburst
41
42#
43# To configure a specific server, such as an organization-wide local
44# server, add lines similar to the following.  One or more specific
45# servers can be configured in addition to, or instead of, any server
46# pools specified above.  When both are configured, ntpd first adds all
47# the specific servers, then adds servers from the pool until the tos
48# minclock/maxclock targets are met.
49#
50#server time.my-internal.org iburst
51
52#
53# Security:
54#
55# By default, only allow time queries and block all other requests
56# from unauthenticated clients.
57#
58# The "restrict source" line allows peers to be mobilized when added by
59# ntpd from a pool, but does not enable mobilizing a new peer association
60# by other dynamic means (broadcast, manycast, ntpq commands, etc).
61#
62# See http://support.ntp.org/bin/view/Support/AccessRestrictions
63# for more information.
64#
65restrict default limited kod nomodify notrap noquery nopeer
66restrict source  limited kod nomodify notrap noquery
67
68#
69# Alternatively, the following rules would block all unauthorized access.
70#
71#restrict default ignore
72#
73# In this case, all remote NTP time servers also need to be explicitly
74# allowed or they would not be able to exchange time information with
75# this server.
76#
77# Please note that this example doesn't work for the servers in
78# the pool.ntp.org domain since they return multiple A records.
79#
80#restrict 0.pool.ntp.org nomodify nopeer noquery notrap
81#restrict 1.pool.ntp.org nomodify nopeer noquery notrap
82#restrict 2.pool.ntp.org nomodify nopeer noquery notrap
83#
84# The following settings allow unrestricted access from the localhost
85restrict 127.0.0.1
86restrict ::1
87
88#
89# If a server loses sync with all upstream servers, NTP clients
90# no longer follow that server. The local clock can be configured
91# to provide a time source when this happens, but it should usually
92# be configured on just one server on a network. For more details see
93# http://support.ntp.org/bin/view/Support/UndisciplinedLocalClock
94# The use of Orphan Mode may be preferable.
95#
96#server 127.127.1.0
97#fudge 127.127.1.0 stratum 10
98
99# See http://support.ntp.org/bin/view/Support/ConfiguringNTP#Section_6.14.
100# for documentation regarding leapfile. Updates to the file can be obtained
101# from ftp://time.nist.gov/pub/ or ftp://tycho.usno.navy.mil/pub/ntp/.
102# Use either leapfile in /etc/ntp or periodically updated leapfile in /var/db.
103#leapfile "/etc/ntp/leap-seconds"
104leapfile "/var/db/ntpd.leap-seconds.list"
105
106# Specify the number of megabytes of memory that should be allocated and
107# locked. -1 (default) means "do not lock the process into memory".
108# 0 means "lock whatever memory the process wants into memory". Any other
109# number means to lock up to that number of megabytes into memory.
110# 0 may result in a segfault when ASLR with stack gap randomization
111# is enabled.
112#rlimit memlock 32
113