Re: [munin-users] ntp_statistics problems

[Helmut W. <hel...@gm...>]

Lupe Christoph wrote:

> Please send the output of
>   ntpq -c "hostnames no" -c peers

via1:/# ntpq -c "hostnames no" -c peers
      remote           refid      st t
======================================
-81.169.158.205  192.53.103.103   2 u
x193.204.114.232 .IEN.            1 u
-212.82.32.15    .PPS.            1 u
+192.168.0.11    .SHM.            1 u
*127.127.28.0    .SHM.            0 l
-217.19.37.20    192.53.103.103  14 u
-193.81.13.2     131.188.3.220    2 u
-194.158.155.98  131.130.1.11     3 u
+192.53.103.104  .PTB.            1 u
  127.127.1.0     LOCAL(0)        13 l

And ntpq at two different moments:
via1:/# ntpq -p
      remote           refid      st t
======================================
-change2linux.co 192.53.103.103   2 u
xntp1.ien.it     .IEN.            1 u
-212-82-32-15.ip .PPS.            1 u
+via2.nack.at    .SHM.            1 u
*SHM(0)          .SHM.            0 l
-nav.metrologie. 192.53.103.103  14 u
-mbox.eunet.at   131.188.3.220    2 u
-orfroufh5.apa.n 131.130.1.11     3 u
+ntp2.ptb.de     .PTB.            1 u
  LOCAL(0)        LOCAL(0)        13 l

via1:/# ntpq -p
      remote           refid      st t
======================================
-change2linux.co 192.53.103.103   2 u
xntp1.ien.it     .IEN.            1 u
-212-82-32-15.ip .PPS.            1 u
+via2.nack.at    .SHM.            1 u
*SHM(0)          .SHM.            0 l
-nav.metrologie. 192.53.103.103  14 u
-mail.sime.com   130.149.17.21    2 u
-orfroufh5.apa.n 131.130.1.11     3 u
+ntp2.ptb.de     .PTB.            1 u
  LOCAL(0)        LOCAL(0)        13 l

The server definitions:
via1:/# cat /etc/ntp.conf | grep \^server
server europe.pool.ntp.org
server ntp1.ien.it
server time1.one4vision.de
server 192.168.0.11
server 127.127.28.0 mode 1 prefer
server time.metrologie.at
server ntp.austria.eu.net
server ts1.orf.at
server ptbtime2.ptb.de
server 127.127.1.0


> The plugin uses the IP addresses and does a reverse lookup with
> gethostbyaddr() on them. That's also the reason you don't see SHM(0) and
> LOCAL(0). 

I understand.
So we can distinguish the following cases:

Case 1:
The real server changes at start of ntpd. This is the case in using 
*.pool.ntp.org, where they have a sort of round robin.

Case 2:
The name does not resolve, because of DNS(-entry) missing.

Case 3:
The same IP has different results after gethostbyaddr() - a sort of 
"reverse round robin". This is the case with ntp.austria.eu.net, which 
resolves as mbox.eunet.*, mail.sime.*, endjinn.austria.*, 
relay2.austria.* etc.

Case 4:
A new server is added to /etc/ntp.conf and ntpd is restarted.

>>2nd Problem:
>>------------
>>The peers are sorted alphabetically. I would prefer them in the order of 
>>ntp.conf=ntpq.

> That's what Munin always does. The plugin delivers the output as it
> reads the ntpq output, but sequence information is lost.

The sequence (in /etc/ntp.conf) is the only reliable index - IMHO. 
Except someone edited but did not restart ...
Thus the IPs of ntpq -c "hostnames no" -c peers are reliable and unique.
Except for *.pool.ntp.org ...

>>3rd Problem:
>>------------
>>The first entry of the ntpq output is europe.pool.ntp.org in ntp.conf 
>>and changes each time after restart of ntp. Therefor I would like to 
>>label it europe.pool.ntp.org.

> That's hard to do. The plugin is written the way it is because ntpq
> truncates the host names. I haven't found a way to get the complete host
> names through ntpq.

ACK.
I will think about a solution. But first I have to configure other things.

Thanks.

Helmut Wollmersdorfer