Syncing woes: iMac does not wake up

Hi all
I have an iMac at work and a Macbook Pro at home. I was very enthusiastic about the arrival of real bidirectional sync in version 2.5 and when the shiny new iMac arrived I could initiate screensharing sessions from home and the next day I set up DTPO and testing the MBP next to the iMac syncing worked fine. Tonight (i.e. at home) I am back to the situation I had hoped to have left behind me: Nothing works, no syncing
“(Direct Connection) Could not open the connection (the specified host could not be found.”
no screensharing session, nothing, just a timeout.

This is likely not Devonthink’s fault but I would greatly appreciate any help because Devonthink is by far my number one reason to get syncing running reliably.

Prion

Sync will not wake up your Mac to Sync.

I did not mean to imply that.
I normally establish a VPN and afp:// connection to the computer before attempting to sync Devonthink. When everything works, that is, which it does not now.

I only mentioned it to get some feedback if other people are managing a similar setup without problems.

Prion

I’ve used Caffeine (the app, not the chemical) to keep my MacBook Air awake when it is connected to external Thunderbolt drives (a Thunderbolt bug causes external drives to think they were improperly disconnected when the host falls asleep). Caffeine is more reliable than OS X’s energy saver settings, IMO. It is a brute force solution, not kind on your energy bills, but it works.

Thanks for the empathy, korm, I am about to go the same route. I know I am not alone for various forums are full of reports of people who are unable to wake up their Macs over Ethernet connections.
I was grumpy that my first iMac had this symptom but simply accepted that as a fact. To discover that the shiny 2013 iMac has the exact same problem, meanwhile the Apple knowledge base is happy to state that under such circumstances one should tick the box saying “Wake on LAN” and that’s it. As if…grrr.
Thanks nonetheless
Prion