Upgrade Postgres RDS in AWS fails major version upgrade

Question

I have been attempting to upgrade our AWS RDS Postgres from 11.22 to 12.17 and/or 15.5

In both instances I get the following error in the error log:

executing: SELECT datname, datallowconn FROM pg_catalog.pg_database All non-template0 databases must allow connections, i.e. their pg_database.datallowconn must be true

When examining those values after the failure I see: enter image description here

So where should I go from here?

Answer 1

You'd go to your preferred interactive database client and run the following statement:

ALTER DATABASE template_postgis ALLOW_CONNECTIONS TRUE;

You can restore the old state after the upgrade.