The standard procedure for upgrading Postgres appears to require that I temporarily run both the old and the new version. This means that I have to change the port of the old version.
This seems completely unnecessary, given how I’m telling
pg_upgrade exactly where to find the data directories and it could just go and read all the data directly.
Is this really the only way to upgrade (apart from dump/restore), or am I misunderstanding something? Can I not just ask the upgrader to convert all the binary data files directly, without messing with users, passwords and ports?