With the recent (2009-12-23) update to FreeBSD's sysutils/smartmontools port smartctl stopped working if run as non-root. I did not investigate whether it is because of the change in the way smartctl operates, or whether it just stopped to be setuid root.

Normally I don't mind going root to run smartctl by hand, but it presents a bit of a problem for the hddtemp_smartctl Munin plugin.

One possible solution is to add the munin user to the operator group, add the following two lines to /etc/devfs.conf:

perm ata 0660
perm xpt0 0660

And finally, run sh /etc/rc.d/devfs restart.

Being the dummy that I am, I only thought about a simpler solution when composing this post: just add user root into the [hddtemp_smartctl] section of your munin/plugin-conf.d/plugins.conf file. Besides being simpler, this method has an added advantage: an updated version of the sysutils/munin-node port can easily incorporate this change. Dag-Erling: hint, hint.