Request clarification w/ PG_DUMPALL -d.

I'm trying to migrate a 9.5 DB to a current version using PG_DUMPALL.

It reclaims that what I pass in the -d parameter is missing a "=" and the man directs me to look at chapter 31.1.1 Connection Strings of the dox PDF.

The Problem is that there are different connection strings listed there and I don't know which one I should use.

Would be happy if somebody could clarify exactly what value/s I need to use for the -d parameter of PG_DUMPALL.