On Wed, Apr 14, 2010 at 01:29:23PM -0400, Lewis Kapell wrote:
> In the documentation under the heading "Migration Between Releases" we
> read:
>
> <<It is also possible to use replication methods, such as Slony, to create
> a slave server with the updated version of PostgreSQL. The slave can be on
> the same computer or a different computer. [...] Such a switch-over results
> in only several seconds of downtime for an upgrade. >>
>
> In the section "Warm Standby Servers for High Availability" it says:
>
> << For testing purposes, it is possible to run both primary and standby
> servers on the same system. >>
>
> Although this section does not use the term Point-In-Time Recovery, I
> understand this is what it refers to. Could the WAL/PITR method then be
> used to upgrade from 8.3 to 8.4 on the same server and avoid having the
> significant downtime of dump/restore?
>
> If so, I understand the two servers would have to run on different ports.
> Are there any other issues/traps to be aware of?
>
> --
>
> Thank you,
>
> Lewis Kapell
> Computer Operations
> Seton Home Study School
>
I believe that the server versions must be the same in PITR so
you cannot use it to upgrade.
Cheers,
Ken