pg_upgradecluster upgrades an existing PostgreSQL server cluster (i. e. a
collection of databases served by a postmaster instance) to a new version
specified by newversion (default: latest available version). The
configuration files of the old version are copied to the new cluster.
The cluster of the old version will be configured to use a previously unused
port since the upgraded one will use the original port. The old cluster is not
automatically be removed. After upgrade, please verify that the new cluster
indeed works as expected; if so, you should remove the old cluster with
pg_dropcluster(8).
HOOK SCRIPTS
Some PostgreSQL extensions like PostGIS need metadata in auxiliary tables which
must not be upgraded from the old version, but rather initialized for the new
version before copying the table data. For this purpose, extensions (as well as
administrators, of course) can drop upgrade hook scripts into
/etc/postgresql-common/pg_upgradecluster.d/ . Scripts in that
directory will be called with the following arguments:
