Re: Issue upgrading from 9.5 to 13 with pg_upgrade: "connection to database failed: FATAL: database "template1" does not exist" - Mailing list pgsql-general

Jeremy Wilson <jwilson@clover.co> writes:
>> On Nov 13, 2020, at 10:09 AM, Adrian Klaver <adrian.klaver@aklaver.com> wrote:
>> In your previous post you had --socketdir=/var/run/postgresql/. Did you change that or is it missing?

> Sorry, here it is with the socket directory specified.

An incorrect socket-directory setting would lead to something like
"could not connect to server: No such file or directory", not to a
specific complaint about a database not being present.

Unless ... could it be that there is another PG server active on the
machine, whose cluster lacks a "template1" database?  Seems unlikely,
but you might try confirming with "ps auxww | grep post" or the like.

I also wonder if the cluster you're trying to upgrade from has a
"template1" database.  Not sure if anyone has ever tested whether
pg_upgrade can cope with the lack of one.

            regards, tom lane