Quote Originally Posted by georgekar View Post
Another idea.
We can save status info on each device. One info is the last master. So any pc insert to the net of devices, ask for a specific device if it's granted or not, and if is ok take the ownership but writing to stat us info the code id.
So we need a master overlordo pc that can reset every device to stand by condition. So for every day use, any pc can operate devices and before shut down mast restore the status info.
Any other pc can read if a device is available, and if not can determine which pc grant it, and maybe can asc to take control. This swap control is a later change of status info, by a key provided from last master of the device.
That's basically the same P2P approach, LaVolpe already outlined (in more detail) in post #9.

The problem with that is to ensure *reliably* reaching "all other PCs" - because
when not reaching *all* of them per Ethernet, you might miss the currently active Master,
ending up with two Masters.

The other problem (or slightly related to that) is *reliably* taking over ownership,
when a current Master goes down (what if the machine or the process which answers
the Ethernet-requests, goes down unexpectedly, without a chance to hand over the
Master-Status, the other clients possibly ending up with "no Master" - one that is not
reachable, running into LAN-connect-TimeOuts and stuff...).

There's quite a lot of possible fallacies with such an approach which need to be solved -
and a load of testing involved - taking days, maybe a week, until such a thing might run
relative well (also depending on the size of the LAN and the reliablity of the Ethernet-
connections there).

The question I was asking is, if that week of work worth a 50-200$ device which
takes up low power and can remain "always on" (playing central server).

Olaf