[rrd-users] rrd insert problem

[Shahar Fleischman]

Hi,
This is my first post to a mailing list so I hope I'm replying
correctly.

After replacing N: with ${now}: I sometimes get this error in the log
file:
+ /usr/local/rrd/bin/rrdtool update /usr/local/rrd/db/host/file.rrd
1212497523:786
ERROR: illegal attempt to update using time 1212497523 when last update
time is 1212497523 (minimum one second step)
although I see the data in the rrd db file correctly:
<!-- 2008-06-03 15:52:00 IDT / 1212497520 --> <row><v> 7.8635000000e+02
</v></row>
Also I have another question, what if there is no data after the N: in
the update command, because I had one time that I had no data and in the
rrd db I saw a very low value like below ?
+ /usr/local/rrd/bin/rrdtool update /usr/local/rrd/db/host/file.rrd N:
<!-- 2008-06-03 15:19:00 IDT / 1212495540 --> <row><v> 5.0322736750e+01
</v></row>


This is my ntp.conf file
########################################################################
#############
driftfile /var/lib/ntp/drift
fudge   127.127.1.0 stratum 10
keys /etc/ntp/keys
restrict 127.0.0.1
restrict 0.rhel.pool.ntp.org mask 255.255.255.255 nomodify notrap
noquery
restrict 1.rhel.pool.ntp.org mask 255.255.255.255 nomodify notrap
noquery
restrict 2.rhel.pool.ntp.org mask 255.255.255.255 nomodify notrap
noquery
restrict -6 ::1
restrict default kod nomodify notrap nopeer noquery
server 127.127.1.0
server 0.rhel.pool.ntp.org
server 1.rhel.pool.ntp.org
server 2.rhel.pool.ntp.org
########################################################################
#############

Thanks for the help.
Shahar.

-----Original Message-----
From: Andreas Maus [mailto:a.maus at science-computing.de] 
Sent: Tuesday, June 03, 2008 3:25 PM
To: Shahar Fleischman
Cc: rrd-users at lists.oetiker.ch
Subject: Re: [rrd-users] rrd insert problem

On Tue, Jun 03, 2008 at 05:15:35AM -0700, mobi wrote:
> hi,
Hi.

> /usr/local/rrd/bin/rrdtool update /usr/local/rrd/db/host1/test.rrd 
> N:1239 and i get no error on insert, but when i look in the graph or 
> dump the rrd this also doesnt happen all the time, but only some time
with no pattern.
> anyone has a clue what can it be ?
Time drift? I've seen something like that on systems with a unstable
system clock and without ntp.

Try using the correct time (date +'%s' on Linux) instead of N.
e.g.:

now=`date +'%s'`
rrdtool update [...] ${now}:[...]

(and check the values of $now)
and of course run ntp to keep your system time stable.

HTH,

Andreas.

-- 
Dipl.-Ing. Andreas Maus             science+computing ag
System Administration               Hagellocher Weg 73
tel.: +49 7071 9457 671             72070 Tuebingen, Germany
fax: +49 7071 9457 411              www.science-computing.de