[rrd-users] setting last_update

Dan Langille dan at langille.org
Thu Feb 15 14:11:06 CET 2007


My short term goal is to reset last_update in an rrd file.  Long 
term, I'd like to find the cause of the very large value contained 
therein.

The problem occurs on a system running FreeBSD 6.2 with an amd64 
kernel.

I encountered these errors yesterday:

rrd_update:illegal attempt to update using time 1171508010 when last 
update time is 94450340160

The first date looks OK. The second does not.

Looking at the rrd file:

# rrdtool info  cpu0.rrd | head
filename = "cpu0.rrd"
rrd_version = "0003"
step = 5
last_update = 944503401600


Notice the date, that's a bit odd:

# date -r 944503401600
Wed Feb 14 00:00:00 PST 31900


This was with rrdtool-1.2.19_1 on FreeBSD 6.2-STABLE #6: Fri Feb  9 
15:54:22 PST 2007 

The rrd file was create using a tool supplied with symon 
(http://www.xs4all.nl/~wpd/symon/).  I followed the same creation 
steps on another system, this one an i386, with a slightly different 
rrdtool, I get better results:

# /usr/local/share/symon/c_smrrds.sh cpu0
cpu0.rrd created
# rrdtool info cpu0.rrd | head
filename = "cpu0.rrd"
rrd_version = "0003"
step = 5
last_update = 1171429200
# date -r 1171429200
Wed Feb 14 00:00:00 EST 2007

Now that's something a little more reasonable.

Failing a solution, does anyone know how to reset the last_update 
field in an rrd file?

-- 
Dan Langille : Software Developer looking for work
my resume: http://www.freebsddiary.org/dan_langille.php
PGCon - The PostgreSQL Conference - http://www.pgcon.org/




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