Cacti Segfaulting on CentOS5

I was getting Cacti set up and was having trouble with PHP. Specifically, it appeared that enabling the Cacti cron job caused a PHP segfault. I looked in /etc/cron.d/cacti to see what was being run:

cat /etc/cron.d/cacti
#*/5 * * * * cacti /usr/bin/php /usr/share/cacti/poller.php > /dev/null 2>&1


Then I ran it from the command line myself:

# php -v
PHP 5.1.6 (cli) (built: Jan 13 2010 17:13:05)
Copyright (c) 1997-2006 The PHP Group
Zend Engine v2.1.0, Copyright (c) 1998-2006 Zend Technologies

# php /usr/share/cacti/poller.php
Segmentation fault


Sure enough, an ugly error was recorded in /var/log/messages:

kernel: php[5250]: segfault at bf29ce64 ip b788cbf3 sp bf29cdc4 error 6 in libc-2.5.so[b7851000+13f000]


It turns out that this is what happens when you bork the permissions on cacti's MySQL table. After issuing a command like the following to MySQL, my segfault went away.

GRANT ALL ON cacti.* TO 'cactiusername'@'localhost' IDENTIFIED BY 'secret';