Logger.conf setup
By default, Asterisk/Freepbx installs with full (debug and verbose) logging enabled. This generates a significant amount of extra write activity to the hard drives and creates a very large "var/log/asterisk/full" log file in a short amount of time. After the initial settling in period when debug logging is no longer required it is a good idea to disable this to reduce the stress on the drives and extend their life.
nano /etc/asterisk/logger.conf
change
full => notice,warning,error,debug,verbose
to
full => notice,warning,error,verbose
you will need to restart Asterisk or type LOGGER ROTATE at the CLI to get this change to take effect (reload doesn't do it apparently).