Occasional disk oddity

[Rob Munsch]

Hello,

On one of my systems today, disk went yellow for a single poll period 
for no apparent reason.  Next poll, it was green again.

The only message I saw in clientdata.log was:

2007-02-16 14:32:33 Host kiwi.tbb (linux) sent incomprehensible disk 
report - missing columnheaders 'Capacity' and 'Mounted'
root     10378    2007-02-16 14:32:33 Adding to combo msg: status 
kiwi,tbb.disk yellow Fri Feb 16 14:32:27 EST 2007 - Filesystems NOT ok

for that single period.  The machine is linux on a 2.6.14 kernel. 
Commandline df output gives me

rmunsch at kiwi:~$ df
Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/sda2               995992     88244    907748   9% /
/dev/mapper/root_vg-home
                       10485436    313516  10171920   3% /local
/dev/mapper/root_vg-tmp
                        5242716    444380   4798336   9% /tmp
/dev/mapper/root_vg-usr
                        2097084    983360   1113724  47% /usr
/dev/mapper/root_vg-var
                       10485436   6633796   3851640  64% /var
date.tbb:/home       136310720  78900608  57410112  58% /home
date.tbb:/shared       2097088    661296   1435792  32% /shared
rmunsch at kiwi:~$

and, as i said, it's now (and usually) green.  What causes this 
anomalous poll?