pf@xxxxxxxxxxx writes: > On Sun, 15 Jan 2023 14:47:35 -0500 Tom Lane wrote: >> I think you misunderstand how this is supposed to work. The -D >> argument should point at an *empty* data directory that has been >> freshly initialized with the new version's initdb. pg_upgrade then >> transfers data into that from the old database (-d argument). > I was hoping to avoid the hours worth of copying to the NVMe SSD. > The instructions refer to upgrading with --link; would that save the copy > time? Yes, but to use --link you must have both data directories on the same filesystem, so this is still the wrong thing. Try something like mv /mnt/work/var/lib/pgsql/data /mnt/work/var/lib/pgsql/data13 initdb /mnt/work/var/lib/pgsql/data pg_upgrade ... -d /mnt/work/var/lib/pgsql/data13 -D /mnt/work/var/lib/pgsql/data --link ... regards, tom lane