I recently bought a NAS (Linkstation from Buffalo) with a sleep function and means to wake it via LAN. Problem was that Buffalo provided no tool for waking it from Mac OS. There are free tools for OS X that give you means for scanning you network and waking up a specific device as WakeOnLan. This tool even has a feature to schedule sending of the WOL package, so you don’t have to do this by hand. But the shortest period is 5 mins and the Linkstation falls asleep after 3 mins.
So, I though a little DIY might help and I wrote a little deamon for waking sending the WOL package after a free configurable period of time, that runs in background. It can be found here (Mac WOL Deamon). It uses the basic Java code from here (wake-on-lan).
Installation can be performed by calling ./install.sh from the terminal. The IP and MAC adress must be entered in the conf.txt within the folder in applications. These can be dicovered using WakeOnLan. Remember to disable the DHCP of your NAS, as this could mean a different IP when your router or NAS restarts. The period is set to to 2 mins. But it can be configured via the /Users/janhelwich/Library/LaunchAgents/helwich.wakeonlan.WakeOnLan.plist.
When you have questions/problems/recommendations don’t hesitate to ask.