Is DRBD split-brain handler called only when after-sb-Xpri is set to disconnect?

Question

I wanted to run a script if a split brain is detected. In the documentation, it is mentioned that we can do that by providing the path of the script like

resource <resource>
  handlers {
    split-brain <handler>;
    ...
  }

But, below that, for the after-sb-0pri configuration, it is mentioned that

disconnect: Do not recover automatically, simply invoke the split-brain handler script (if configured), drop the connection and continue in disconnected mode.

So, my question is that, will the configured script be run only when after-sb-0pri is set to disconnect, or will that run for any set value

Document Link: https://linbit.com/drbd-user-guide/users-guide-drbd-8-4/#s-configure-split-brain-behavior

Answer 1

DRBD should invoke the split-brain handler whenever a split-brain is detected. I.E. Anything that would log a Split-Brain detected ... in the system/kernel logs. The documentation attempts to explain this at the beginning of chapter 5.17.1 with:

DRBD invokes the split-brain handler, if configured, at any time split brain is detected.

Additionally, disconnect is the default value for after-sb-0pri. So, even if not explicitly set that will still be the behavior.