Our previous ntp.conf file configured 3 servers from freebsd.pool.ntp.org
using 3 separate 'server' config lines. That is now replaced with a single
'pool' line which causes ntpd to add multiple servers from the pool.
More than just making the config smaller, the pool feature in ntpd has one
major advantage over configuring 3 separate servers from a pool: if a server
that was added using a 'pool' statement provides bad time (initially or at
some later date), ntpd automatically discards it and configures a new
different server from the pool without needing to be restarted.
These changes also add a 'tos' line to control how many pool servers get
added, a 'restrict source' line that is required to allow ntpd to add new
peers from the pool, and it deletes a 'restrict 127.127.1.0' line that does
nothing and should never have been there (127.127.1.0 is not a valid IP
address, it's a refclock identifier).
Differential Revision: https://reviews.freebsd.org/D9011
The working copy of leapfile resides in /var/dbntpd.leap-seconds.list.
/etc/ntp/leap-seconds (periodically updated from ftp://time.nist.gov/pub/
or ftp://tycho.usno.navy.mil/pub/ntp/) contains the master copy should
automatic leapfile updates be disabled (default).
Automatic leapfile updates are fetched from $ntp_leapfile_sources,
defaulting to https://www.ietf.org/timezones/data/leap-seconds.list,
within $ntp_leapfile_expiry_days (default 30 days) from leap-seconds
file expiry. Automatic updates can be enabled by setting
$daily_ntpd_leapfile_enable="YES" in periodic.conf. To avoid congesting
the ntp leapfile source the automatic update randomized by default but
can be disabled through daily_ntpd_avoid_congestion="NO" in
periodic.conf.
Suggested by: des
Reviewed by: des, roberto, dwmalone, ian, cperciva, glebius, gjb
MFC after: 1 week
X-MFC with: r289421, r293037
leap second date correct
Updates to the file can be obtained from ftp://time.nist.gov/pub/ or
ftp://tycho.usno.navy.mil/pub/ntp/.
Suggested by: dwmalone
Reviewed by: roberto, dwmalone, delphij
Approved by: roberto
MFC after: 1 week
to NTP access restriction documentation.
The new default restrictions would allow only time queries from a
remote system and will KoD all other requests, but still allow
localhost to do make all requests.
These restrictions are also recommended for all Internet-facing
public NTP servers.
This changeset is intended for an instant MFC to stable/10 and
releng/10.0.
2) Point people at the pool website and encourage
people to provide a server in the pool (as a
courtesy to the pool guys).
3) Fix a spelling.
4) Comment out the local clock and include a link
to documentation for use of the local clock on
the ntp.org site.
Approved by: re (kib)
This NTP configuration file points to the [012].pool.ntp.org servers,
which will return a list of geographical local NTP servers.
It uses the best-practice options of "iburst" and "maxpoll 9".
It gives examples on how to use the "restrict" commands, which are
unfortunately not working when you use the pool.ntp.org servers.
It sets up a fudge server so any clients syncing against this server
will always be synced even if we lose the master.
The idea of this file was briefly discussed on -net.
PR: conf/58595
Submitted by: Chris Stenton <jacs@gnome.co.uk>
MFC after: 1 week
