> Richard Huxton wrote:
> > Jason Long wrote:
> >> I need to set up master vs slave replication.
> >> My use case is quite simple. I need to back up a small but fairly
> >> complex(30 MB data, 175 tables) DB remotely over T1 and be able to
> >> switch to that if the main server fails. The switch can even be a
> >> script run manually.
> >> Can someone either comment in as much detail as possible or point me to
> >> a comparison of Slony vs Longiste. Or some other option I have not
> >> heard of?
> > Three questions you need to ask yourself.
> > 1. How heavily updated is the database?
> > 2. How often do you change the database's schema?
> > 3. Are there other databases in the installation?
> > If #1 is "very heavy" then you'll want to do some testing with any
> > solution you use.
> > If #2 is "a lot" then you'll want to consider WAL shipping as mentioned
> > below. Slony can handle schema changes, but you'll need to process them
> > through its own script. I'm afraid I can't comment on Londiste.
> > If you just want a backup and the answer to #3 is no, look at WAL
> > shipping (see the various archive_xxx config settings in the manual and
> > google a bit).
> >> From what I read Longiste is easy to set up while I got a quote for
> >> Slony setup for 5-10k.
> > Unless your requirements are strange, that seems a little high, even
> > assuming USD as a currency. Of course, if you want support and
> > maintenance that will tend to make things mount.
> The database has 10-20 concurrent users so updates are not very heavy.
> The schema changes very frequently.
> There are not other databases in the installation.
> This quote included initial setup, failure testing, and scripts that
> were to automate setup and manage the installation. It did not include
> support and maintenance.
Are you planning on hiring someone to do it, or are you going to do it
yourself, because the prices of the solution is completely orthogonal to
which is the better fit technically.
In your case, since you do a lot of DDL changes, I'd go with londiste over
slony if I had to pick from those two. However, given the requirements you
laid out, PITR is probably your best option (this is what Richard alluded
too), and certainly the one I would recommend you try first.
Database: Scalability: Consulting