Stuff…

The cacti RRA files that were being update by the crontab:

/usr/bin/php /usr/share/cacti/poller.php

stopped working for some reason.  No permissions had changed, but, the disk did fill up at one start.  It was thought that perhaps some of the RRA files had been corrupted, however, running rrdtool info and fetch on the files they worked fine.

It turned out to be the php.ini files memory setting be set to 8M.  Updated this to 64MB and the poller started working again.

This was a useful document on the cacti site:

http://www.cacti.net/downloads/docs/html/check_rrd_updating.html