Can is start the plex server from a client?

and wake up the imac?
otherwise what is the use streaming if i need to walk to the server anyhow…

I think this has been asked many times. You may want to do a search for SLEEP or WAKE. You may find the answers you are looking for.

A server is always on!

And no Plex client supports WOL (Wake on LAN)
You might be able to use 3.Party tools, if on the same LAN as the server though

there are lot of posts about getting imac server out of sleep mode… but i cannot find the answer…

thank you, this helps. I will stop searching …