Re: A few user-level questions on Streaming Replication and pg_upgrade

Gurjeet Singh wrote:

[  CC to general removed --- emailing only hackers;  cross-posting is
frowned upon. ]

> .) Is Streaming Replication supported across minor releases, in reverse
> direction; e.g. 9.0.3 to 9.0.1
>
>     I think the answer is "it depends", since it would depend upon whether
> any SR related bug has been fixed in the 'greater' of the minor releases.
>
>     I am assuming that smaller minor release to bigger minor release will
> always be supported (e.g. 9.0.1 to 9.0.3)

Yes.

We could mention in the minor release notes if we break streaming
replication for a minor release --- or someone will tell us when we do.

> .) How reliable is `pg_upgrade -c` (dry run) currently; that is, how
> accurate is pg_upgrade at predicting any potential problem with the eventual
> in-place upgrade.
>
>     I'd say it is as reliable as it gets since this is the official tool
> supported by the project, and it should not contain any known bugs. One has
> to use the latest and greatest 'minor' version of the tool for the major
> release they are upgrading to, though.

Well, we make no guarantees about the software at all, so it is hard to
make any guarantee about pg_upgrade either.