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Message-ID: <98182efc-eb12-42f0-8016-01163b5c6fcb@aklaver.com>
Date: Tue, 10 Jun 2025 13:14:50 -0700
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Subject: Re: pg_upgradecluster version 10 to 16 question
To: Jim Cunning <jlcunning46@gmail.com>, pgsql-general@lists.postgresql.org
References: <cb7713f2-8ff9-42eb-a3fa-a89c4dc8257a@gmail.com>
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From: Adrian Klaver <adrian.klaver@aklaver.com>
In-Reply-To: <cb7713f2-8ff9-42eb-a3fa-a89c4dc8257a@gmail.com>
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On 6/10/25 13:01, Jim Cunning wrote:
> I had a Ubuntu 20.04 LTS system with a postgresql version 10 database, 
> and the system became unbootable.  The database was stored in 
> /var/lib/postgresql/10/main and I was able to recover the entire 
> contents of the data in that directory and below.  I now have a system 
> running ubuntu 24.04 LTS with postgresql version 16.
> 
> I obviously no longer have a running version 10 server, so I cannot use 
> pg_dump to retrieve the data.  I have placed the recovered version files 
> in /var/lib/postgresql/10/main on my new system, alongside the 
> /var/lib/postgresql/16/main that was created when I installed 
> postgresql.  I have tried several iterations of the pg_upgradecluster 
> command, a Python script provided by Ubuntu, but it says it cannot find 
> the database files.
> 
> I also see from the postgresql wiki pages that there is a pg_upgrade 
> utility program, but cannot find in any of the Ubuntu-provided 
> installation files.  Can anyone provide some guidance on how I might 
> proceed?

1) Do:

man pg_upgradecluster

2) Assuming you used the PGDG repos to install Postgres you can do:

sudo apt install postgresql-10

to get a Postgres 10 install. I would move the 
/var/lib/postgresql/10/main you created out of the way and then move the 
contents back in to the installed version.

> 
> Thanks in advance.
> 

-- 
Adrian Klaver
adrian.klaver@aklaver.com