Shell Programming and Scripting

#server 127.127.1.0

#fudge 127.127.1.0 stratum 10

server 192.168.122.76

const='tinker panic 0'
if [ -e /etc/ntp.conf ]; then
  grep -q -e "$const" /etc/ntp.conf
  if [ $? = 1 ]; then
    echo "$const  ; not found but will be inserted as first line!"
    sed -i.bak '1 i\tinker panic 0' /etc/ntp.conf
  fi
# Add '#' to beginning of line if it is not already there
# to disable the local clock.
sed -i.bak \
    -e 's/^server 127.127.1.0$/#server 127.127.1.0/' \
    -e 's/^fudge  127.127.1.0 stratum 10$/#fudge 127.127.1.0 stratum 10/' \
    -e 's/^server 192.168.122.76$/server 192.168.122.76/' /etc/ntp.conf
fi

tinker panic 0
tinker panic TEST 0
# Permit time synchronization with our time source, but do not
# permit the source to query or modify the service on this system.
restrict default kod nomodify notrap nopeer noquery
restrict -6 default kod nomodify notrap nopeer 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
restrict -6 ::1
# Hosts on local network are less restricted.
#restrict 192.168.1.0 mask 255.255.255.0 nomodify notrap
# Use public servers from the pool.ntp.org project.
# Please consider joining the pool (pool.ntp.org: Join the NTP Pool!).
#server 0.rhel.pool.ntp.org
#server 1.rhel.pool.ntp.org
#server 2.rhel.pool.ntp.org
#broadcast 192.168.1.255 key 42         # broadcast server
#broadcastclient                        # broadcast client
#broadcast 224.0.1.1 key 42             # multicast server
#multicastclient 224.0.1.1              # multicast client
#manycastserver 239.255.254.254         # manycast server
#manycastclient 239.255.254.254 key 42  # manycast client
# Undisciplined Local Clock. This is a fake driver intended for backup
# and when no outside source of synchronized time is available.
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
# Key file containing the keys and key identifiers used when operating
# with symmetric key cryptography.
keys /etc/ntp/keys
# Specify the key identifiers which are trusted.
#trustedkey 4 8 42
# Specify the key identifier to use with the ntpdc utility.
#requestkey 8
# Specify the key identifier to use with the ntpq utility.
#controlkey 8