Individual tcp-check send (binary) commands per backend server? rand()?

Help!
1

Hello HAProxy community!

I configured a tcp-check using send-binary and expect binary.

The check works fine. To make it perfect and according to the protocol, I need to send an individual string or binary for each backend server.

  1. Is it possible to configure a check individually for each server in a back-end?

  2. Or even better / easier, is it possible somehow to use rand() or reference any dynamic variable in those “tcp-check send” lines?

Thanks in advance for any ideas!
Regards

Christian