Running Slackware-14.2/x86_64. Current installation is postgres-11.5 and I'm upgrading to postgresql-12.1. Both versions are installed and stopped.
If I have correctly read the pg_upgrade manual page this is the command to use (as user postgres) with lines split to fit the message; the command will be on a single line: pg_upgrade \ -b /usr/lib64/postgresql/11/bin/ \ -B /usr/lib64/postgesql/12/bin/ \ -d /var/lib/pgsql/11/data/ \ -D /var/lib/pgsql/12/data/ \ -p 5432 \ -P 5432 I don't know that the port numbers are required. Have I missed an option? Rich
