Re: [MLUG] advantage of ntp over ntpdate (was "Locate NTP Servers")

[Rick Buford <EMAIL:PROTECTED>]

The How-to use NTP in 60 seconds tutorial:

1. get some strata 1 or 2 clocks (there was a link to a URL earlier)
2. each address needs a couple of lines in /etc/ntp.conf
Mine @ home:
server 128.4.40.12              #louie.udel.edu
server 130.126.24.53            #ntp-0.cso.uiuc.edu
server 128.46.103.93            #gilbreth.ecn.purdue.edu
server 128.59.16.20             #timex.cs.columbia.edu
server 128.118.25.3             #clock.psu.edu
server 66.187.233.4             #clock.redhat.com
restrict 66.187.233.4 mask 255.255.255.255 nomodify notrap noquery
restrict 128.4.40.12 mask 255.255.255.255 nomodify notrap noquery
restrict 130.126.24.53 mask 255.255.255.255 nomodify notrap noquery
restrict 128.46.103.93 mask 255.255.255.255 nomodify notrap noquery
restrict 128.59.16.20 mask 255.255.255.255 nomodify notrap noquery
restrict 128.118.25.3 mask 255.255.255.255 nomodify notrap noquery

3. start/restart your ntpd service
4. verify it's working with:
ntpq -pn
[EMAIL:PROTECTED JPG]# ntpq -pn
      remote           refid      st t when poll reach   delay   offset 
  jitter
==============================================================================
-128.4.40.12     128.4.1.1        2 u  648 1024  377   55.711    0.040 
  0.241
*130.126.24.53   128.174.38.133   2 u  568 1024  377  504.587  223.528 
227.772
+128.46.103.93   130.126.24.53    3 u  402 1024  377  544.634  189.123 
235.275
-128.59.16.20    204.123.2.5      2 u  654 1024  377   60.494    2.764 
  0.790
+128.118.25.3    128.118.25.5     2 u  315 1024  377  452.173  209.758 
354.764
  66.187.233.4    67.68.77.65     16 u  45d 1024    0    0.000    0.000 
4000.00

* = the box you're currently sync'ing with
+ = a backup candidate
- = configured

The important numbers to watch here is the "reach" number. 377 equates 
to a binary counter that for every successful contact atttempt, so it 
will initially be 0. The rest of the numbers are not that useful to me, 
because ntp actually does all the calculations for me.

You can also see where one of the clocks I have configured, 67.68.77.65, 
is no longer responding with a "reach" of 0 and 4000 jitter.

5. Profit!!!

Mark Rages wrote:
> On Apr 7, 2005 2:43 PM, Pottinger, Hardy J. <EMAIL:PROTECTED> wrote:
> (a lot of links to documentation and such)
> 
> All those HOWTOs and protocol docs are kind of intimidating to the
> casual admin.  This is what I discovered:  On a Fedora box, go to
> "system settings"->"server settings" and check "ntpd".  Click "start"
> if it's not started. You can change the server in /etc/ntpd.conf, but
> the redhat-provided ones work fine.
> 
> I believe Mike is running Solaris, so he may have to deal with all
> that information, but my distro maintainers have done it for me.
> 
> Regards,
> Mark
> EMAIL:PROTECTED
_______________________________________________
members mailing list
EMAIL:PROTECTED
http://mlug.missouri.edu/mailman/listinfo/members