Re: pg_upgrade 10.2

On 06/12/2018 01:34 PM, Murthy Nunna wrote:
> In older versions of pg_upgrade (e.g from 9.2 to 9.3), I was able to run
> pg_upgrade without stopping old cluster using the check flag.
>
> pg_upgrade -b <old-bin> -B <new-bin> -d <old-data> -D <new-data> -p 5432
> -P 5434 -r -v -k -c
>
> Note the “c” flag at the end

I take the below to it mean it should work:

https://www.postgresql.org/docs/10/static/pgupgrade.html
> "You can use pg_upgrade --check to perform only the checks, even if the
old server is still running. pg_upgrade --check will also outline any
manual adjustments you will need to make after the upgrade. If you are
going to be using link mode, you should use the --link option with
--check to enable link-mode-specific checks."

Might want to try without -k to see what happens.

More comments below.

> However pg_upgrade in 10 (I tried from 9.3 to 10.4), when I did not stop
> the old cluster, the upgrade failed:
>
> ***
>
> There seems to be a postmaster servicing the old cluster.
>
> Please shutdown that postmaster and try again.
>
> Failure, exiting
>
> Is this expected?
>
> Also, when I stopped the old cluster and ran pg_upgrade with “-c” flag,
> the file global/pg_control got renamed to global/pg_control.old. The
> “-c” flag never renamed anything in the old cluster in older pg_upgrade

Again seems related to -k:

"
If you ran pg_upgrade without --link or did not start the new server,
the old cluster was not modified except that, if linking started, a .old
suffix was appended to $PGDATA/global/pg_control. To reuse the old
cluster, possibly remove the .old suffix from $PGDATA/global/pg_control;
you can then restart the old cluster.
"
>

--
Adrian Klaver
adrian(dot)klaver(at)aklaver(dot)com