Linux How to..

TAG : How to install NTP Server บน CentOS5.x

time server for ntpd client at Thailand :
server 203.185.69.60    #time1.nimt.or.th
server 203.185.69.59    #time2.nimt.or.th
server 203.185.69.56    #time3.nimt.or.th
Install NTP Package
#yum install -y ntpd

#cd /etc
#vi ntd.conf

edit line red word :

# 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

# 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 (http://www.pool.ntp.org/join.html).

#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

server 203.185.69.60    #time1.nimt.or.th
server 203.185.69.59    #time2.nimt.or.th
server 203.185.69.56    #time3.nimt.or.th
# 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

# fudge 127.127.1.0 stratum 10

fudge   127.127.1.0 stratum 2
broadcastdelay 0.008

# 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
#server clock.nectec.or.th
#restrict clock.nectec.or.th mask 255.255.255.255 nomodify notrap noquery

:wq!  –> save file above and quit

#vim /etc/ntp/step-tickers
input line :

time1.nimt.or.th
time2.nimt.or.th
time3.nimt.or.th

=================================================================

Sync NTP Server to hardware clock(command line : clock –systohc) when restart ntpd service

#vi /etc/sysconfig /ntpd

edit line below:
SYNC_HWCLOCK=yes
Restart NTP service
#service ntpd restart
Auto start when Restart server
#chkconfig ntpd on