Re: Whereis NTP (client) config file in Red Hat Enterprise Linux 3.

Jean-David Beyer wrote:

> If you right click on the clock applet on the GNOME panel, one of the
> options is "Adjust Date and Time..." If you select that, enter the root
> password, you can select "Enable Network Time Protocol". If you check that
> box, you get a list of NTP time servers (two are 66.187.224.4 and
> 66.187.233.4, which are Red Hat. Two are clock.redhat.com and
> clock2.redhat.com, which have the same IP addresses as the first two).
>
> Right now I am on dial-up and this does not work very well, but I will be
> getting a broadband (15 Megabit/sec Verizon FiOS) in a few days and I
> thought it would be nice to enable this instead of running _rdate_ as I do
> now. But reading about NTP, it suggests using three to five NTP servers,
> and I have a list of available level 2 servers near me. But it seems this
> allows me to use only one.
>
> Is there any easy way to diddle a config file somewhere (where?) to add
> entries to this list, and to tell whatever program uses this (which one?)
> to use them all?

The file is; /etc/ntp.conf

And recent changes (google on pool.ntp.org) make this really easy to
configure, sample file below;

# Permit time synchronization with our time source, but do not
# permit the source to query or modify the service on this system.

restrict default nomodify notrap noquery

# Permit all access over the loopback interface. This could
# be tightened as well, but to do so would effect some of
# the administrative functions.
restrict 127.0.0.1


# -- CLIENT NETWORK -------
# Permit systems on this network to synchronize with this
# time service. Do not permit those systems to modify the
# configuration of this service. Also, do not use those
# systems as peers for synchronization.
# restrict 192.168.1.0 mask 255.255.255.0 nomodify notrap


# --- OUR TIMESERVERS -----
server 0.pool.ntp.org
server 1.pool.ntp.org
server 2.pool.ntp.org


# --- NTP MULTICASTCLIENT ---
#multicastclient # listen on default 224.0.1.1
# restrict 224.0.1.1 mask 255.255.255.255 nomodify notrap
# restrict 192.168.1.0 mask 255.255.255.0 nomodify notrap



# --- GENERAL CONFIGURATION ---
#
# Undisciplined Local Clock. This is a fake driver intended for backup
# and when no outside source of synchronized time is available. The
# default stratum is usually 3, but in this case we elect to use stratum
# 0. Since the server line does not have the prefer keyword, this driver
# is never used for synchronization, unless no other other
# synchronization source is available. In case the local host is
# controlled by some external source, such as an external oscillator or
# another protocol, the prefer keyword would cause the local host to
# disregard all other synchronization sources, unless the kernel
# modifications are in use and declare an unsynchronized condition.
#
server 127.127.1.0 # local clock
fudge 127.127.1.0 stratum 10

#
# Drift file. Put this in a directory which the daemon can write to.
# No symbolic links allowed, either, since the daemon updates the file
# by creating a temporary in the same directory and then rename()'ing
# it to the file.
#
driftfile /var/lib/ntp/drift
broadcastdelay 0.008

#
# Keys file. If you want to diddle your server at run time, make a
# keys file (mode 600 for sure) and define the key number to be
# used for making requests.
#
# PLEASE DO NOT USE THE DEFAULT VALUES HERE. Pick your own, or remote
# systems might be able to reset your clock at will. Note also that
# ntpd is started with a -A flag, disabling authentication, that
# will have to be removed as well.
#
keys /etc/ntp/keys

--
"A personal computer is called a personal computer because it's yours,
Anything that runs on that computer, you should have control over."
Andrew Moss, Microsoft's senior director of technical policy, 2005
.

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