Tomasz Szypowski <tomasz(dot)szypowski(at)gmail(dot)com> writes:
> As far as I remember pg_upgrade is from 11.2 rest is from 9.5.
If you're not certain, run each program with the --version switch
to find out. But pg_upgrade should be refusing to use pg_dump
et al that aren't from its own major version.
regards, tom lane