Re: pg_upgradecluster version 10 to 16 question

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(dot)klaver(at)aklaver(dot)com