Communication between two s7300 Ethernet

Hi

I want to ask several questions.

1- Is it possible to make communication between two s7300 plc via ethernet, WITHOUT hardware download?

Plc is in run mode, I can't stop it. That's why I'm asking.

2- which block will I use? AGSEND AGRECEIVE or PUT GET or something else..

3- Can I use CP343-1 Lean instead of a normal CP343-1?

Will answers change according to plc? ( Now I have two compact plc with cp343-1 module, I want to learn answers for plcs with profinet ports too )

4- I want to ask for Dp/Dp coupler too. Is it for only two plc? Can I use it for data exchange between 5 plc?
Thanks

NB. I assume that this is an existing project with a CPU without an onboard ethernet port.

3. Yes you can use CP343-1 Lean.
2. You can use AG_SEND/AG_RECEIVE. PUT/GET require that the active partner is at least a CP343-1 (not Lean).
1. For CP343-1 Lean or CP343-1 you need to download a HW Configuration with a connection defined in NetPro. So that requires a restart.
4. It will be too cumbersome to use DP Couplers for more than 2 PLCs.

thank you