[ntp:questions] NTP.ORG MEINBERG KEEP TIME ACCURATE to 10MS

gbusenberg at yahoo.com gbusenberg at yahoo.com
Wed Nov 14 21:40:11 UTC 2012


They HP DL 380 G7 Servers.  Sorry for the typo.  No virtual machines are being used.  Each Windows 2008 Server has dedicated hardware and is almost idle in terms of load. Yesterday after making the changes of getting rid of the tinker and server 127.127.1.0 & fudge 127.127.1.0 everything seemed better however after it ran for about 18 hours, I am back to about 250ms offsets in ntpq -p.

I will try the suggestions that Charles made and then if that doesn't work, I will try the latest binaries that David suggested.

server 10.1.126.204 iburst minpoll 5 maxpoll 5
broadcastclient 
broadcastdelay 0.000800  ## in seconds 


I want to give some more detals on my setup just to make sure there is nothing important that I have not shared:

My small network of 8 Windows 2008 Servers & Windows 7 PCs are all on the same 1gbps LAN.  10.1.126.204 is one of my servers and syncs time with 20.200.0.1.  ntpq -p is shown below for 10.1.126.204


     remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
*20.200.0.1      132.163.4.101    2 u  407  512  377    0.051  119.693  37.748

20.200.0.1 only supports NTP Version 3.  On 10.1.126.204, I have my ntp.conf file set as follows

driftfile "C:\Program Files (x86)\NTP\etc\ntp.drift"
server 20.200.0.1 version 3 iburst minpoll 4

I can understand that I would have a hard time keeping good NTP time with 20.200.0.1 since this server doesn't support NTPV4.  The thing I don't understand is why all of my other servers that get their NTP time from 10.1.126.204 using NTPV4 are unable to keep a low offset after the NTP Service has been running for about a day.

Below ntpq -p from my 10.1.126.202 server which gets time from 10.1.126.204.  I see there is a lot of Jitter.  Is the offset of 259ms. 

     remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
*10.1.126.204  20.200.0.1       3 u 1006 1024   77    0.043  -259.69 165.850

driftfile "C:\Program Files (x86)\NTP\etc\ntp.drift"
server 10.1.126.204 iburst minpoll 4

My machines are in a Windows 2008 Domain.  There are no firewalls and all firewalls on the Windows Servers is disabled.  I have verified on all machines that the Windows Time Service is disabled so I am only using the "Network Time Protocol Daemon".

I went through the install guide for windows at:

http://www.satsignal.eu/ntp/setup.html

Greate guide.  Wish the Meinberg site had a link to this (Or maybe it doesn and I just missed it).  Everything looks good on my end except I left the default of installing in Program Files as opposed to C:\Tools which I don't think is my issue.  I will try the steps to upgrade the binaries to 4.2.7p285 in the Guide. Also, I checked Event Viewer on a couple of servers and there are no errors for NTP.



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