NTP Server:
the ntp server can be configured in systemconfig under "Time Date" NTP or via the file /etc/ntp.conf.
# This is the most basic server ntp configuration file
# The driftfile must remain in a place specific to this
# machine - it records the machine specific clock error
driftfile /var/lib/ntp/drift
# local clock
server 127.127.1.0
fudge 127.127.1.0 stratum 10
# Defining a security setting
# only local network access granted
#restrict 192.168.1.0 mask 255.255.255.0 nomodify notrap
Restart the ntp server with the button "Apply" or the command service ntpd restart.
NTP Client:
The ntp client can be configured in systemconfig under "Time Date" NTP or via the file /etc/ntp.conf.
# This is the most basic ntp configuration file
# The driftfile must remain in a place specific to this
# machine - it records the machine specific clock error
driftfile /var/lib/ntp/drift
# ntp polling interval
minpoll 2
maxpoll 2
# Force reading time from Server before starting ntp-client service
ForceFirstSync
# define ntp server list prefer this server and use a fast sync after ntp start
server 192.168.1.124 iburst prefer
# Using local hardware clock as fallback
server 127.127.1.0
fudge 127.127.1.0 stratum 8
# Defining a default security setting
restrict default
Restart the ntp client with the button "Apply" or the command service ntpd restart.
NTP Status:
To check the ntp status use the command ntpstate.
nptstat
or
ntpq -np
Windows W32Time Server:
https://support.microfocus.com/kb/doc.php?id=7015424
This is not a supported configuration. Neither Microsoft nor the Linux community recommends having NTP clients getting their time from the W32Time service that comes standard with Windows server.
The W32Time service cannot be used as a reliable time source for a NTP client daemon. W32Time was designed for Kerberos which has a 5 minute tolerance. The best time resolution W3Time can provide is 1-2 seconds from actual time. Moreover, Windows will accept an offset (time difference) of 1 year with no problem.
The NTP daemon is designed for high accuracy environments. It can resolve time down to 250 picoseconds (trillionths). NTP, by default, not trust anything off by 1000ms and will actually unload if the offset is more than 1000 seconds.
More information can be found here: http://technet.microsoft.com/en-us/library/cc773061%28v=ws.10%29.aspx .
The only supported resolution to this mix of platforms is:
1. Use NTP servers to provide reference time to other NTP clients as well as the Windows servers. It is also recommended to have at least three reference servers. This helps break a tie else when two are in disagreement. The reference servers will, in turn, pull their time from a reliable non-virtualized time source also running NTP.
2. Install a 3rd party NTP application on the Windows server (IE., ntp.org).
Workarround:
Use the Boot Script with a cyclic call of ntpdate <timerserver-ip>