On Fri, May 10, 2013 at 8:43 AM, Carlos Henrique Reimer
<carlos.reimer@opendb.com.br> wrote:
> Hi,
>
> We are developing a solution which will run in thousands of small cash till
> machines running Linux and we would like to use PostgreSQL but there is a
> insecurity feeling regarding the solution basically because these boxes
> would be exposed to an insecure environment and insecure procedures like:
> non controlled power outages, untrusted hardware, no appropriate environment
> for hardware (dusty, hot) etc...
>
> Our major concern is related to the write-back issues we can face in this
> environment. Is there a way to prevent it or a way PG can be configured to
> detect write-back configurations? Don't think so, but...
This is not the job of postgres, but of the operating system (and
possibly various hardware attached to the server). In practice, it's
very possible to configure things so that a full flush all the way to
physical storage is guaranteed -- in fact that's the default behavior
for many configurations. So this part, at least, is trivially done.
> Basically, the question is: is there a way to guaranty a reliable PG
> database in an untrusted and insecure environment? Maybe some kind of file
> system could give this guaranty, not sure..
Again, this has more to do with the hardware (especially) operating
environment and the operating system than postgres itself.
merlin