Read the following tips in securing your Linode Server with cPanel ClamAV.
Log into your WHM and enable the following plugins.
Home > cPanel > Manage Plugins
Enable ClamAV
It takes roughly 40 minutes for installation to complete..
Now to enable your ClamAV scans to be run and visit the accounts cPanel to access virus scans.. A good tutorial on how to do this can be found here.
Beware of redundancies and how much memory your server is operating with.
Resources
Installing ClamAV on a Cpanel server: http://www.thecpaneladmin.com/installing-clamav-on-a-cpanel-server/
spamdconf cPanel plugin: http://forums.cpanel.net/f5/spamd-startup-configuration-spamdconf-tips-46758.html