Re: pg_upgrade with --link then pg_basebackup for replication

On Mon, Nov  2, 2015 at 04:39:02PM -0800, Jorge Torralba wrote:
> Here is an odd question.
>
> If one was to upgrade Postgres to 9.4 from 9.1 using the --link option, then
> setup replication using pg_basebackup, would the standby server preserve the
> hard links with the pg_basebackup or will -D /new/destination/data/dir be a
> clean unlinked version?

I will be clean.  If you want to upgrade the the standby to 9.4 without
a new basebackup, see this blog entry:

    http://momjian.us/main/blogs/pgblog/2015.html#June_10_2015

> Afterwards, if failing over to standby then failing back, would that implement
> a non linked version back on the primary if specifying a new data directory as
> well ?

The links are only created on the server you run pg_upgrade, meaning
normally not on the standby.

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  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

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