Re: Extending BASE_BACKUP in replication protocol: incremental backup and backup format

On Tue, Jan 14, 2014 at 2:41 PM, Andres Freund <andres(at)2ndquadrant(dot)com>wrote:

> On 2014-01-14 14:40:46 +0100, Magnus Hagander wrote:
> > On Tue, Jan 14, 2014 at 2:18 PM, Andres Freund <andres(at)2ndquadrant(dot)com
> >wrote:
> >
> > > On 2014-01-14 14:12:46 +0100, Magnus Hagander wrote:
> > > > Either way - if we can do this in a safe way, it sounds like a good
> idea.
> > > > It would be sort of like rsync, except relying on the fact that we
> can
> > > look
> > > > at the LSN and don't have to compare the actual files, right?
> > >
> > > Which is an advantage, yes. On the other hand, it doesn't fix problems
> > > with a subtly broken replica, e.g. after a bug in replay, or disk
> > > corruption.
> > >
> > >
> > Right. But neither does rsync, right?
>
> Hm? Rsync's really only safe with --checksum and with that it definitely
> should fix those?
>
>
I think we're talking about difference scenarios.

I thought you were talking about a backup taken from a replica, that
already has corruption. rsync checksums surely aren't going to help with
that?

--
Magnus Hagander
Me: http://www.hagander.net/
Work: http://www.redpill-linpro.com/