Upgrading PSQL from 15 to 16, can upgrade client but not server

Question

I have a server in which I wiped and booted with rhel9. I then used this resource to install psql 15 a couple months ago - https://www.tecmint.com/install-postgresql-and-pgadmin-rhel-9/ I am now trying to upgrade to psql16. I have installed pgsql16.

I was able to really quickly switch the client version using a link sudo ln -sf /path/to/psql16 /usr/bin/psql

So now my psql version returns psql (16.1, server 15.3)

But I am unable to update the server version.

Here is the script I am trying to use within the postgres user: /usr/pgsql-16/bin/pg_upgrade -b /usr/pgsql-15/bin/ -d 15/data/ -B /usr/pgsql-16/bin/ -D 16/data/

I am getting this error: Performing Consistency Checks

Checking cluster versions ok

failure Consult the last few lines of "16/data/pg_upgrade_output.d/20240112T172407.795/log/pg_upgrade_server.log" for the probable cause of the failure.

connection to server on socket "/var/lib/pgsql/.s.PGSQL.50432" failed: No such file or directory Is the server running locally and accepting connections on that socket?

could not connect to source postmaster started with the command: "/usr/pgsql-15/bin/pg_ctl" -w -l "16/data/pg_upgrade_output.d/20240112T172407.795/log/pg_upgrade_server.log" -D "15/data" -o "-p 50432 -b -c listen_addresses='' -c unix_socket_permissions=0700 -c unix_socket_directories='/var/lib/pgsql'" start Failure, exiting

The log says: pg_ctl: could not start server

Any help is appreciated.