Обсуждение: Multi master use case?

Hello,

A client of ours has always had problems with slow internet connectivity - they are in a part of the country where that
isa problem. There are a few hundred staff sharing a couple of asymmetric (ADSL) connections. One issue is with
accessingtheir web-based Postgres app, which we host. Now they don't want to run it internally for a lot of the usual
reasons,not least they have many distributed workers and trying to serve data from an already congested spot would be a
nonstarter. 

Is this a case for multi master do you think? I.e. running one on the internet, one locally.

Looking through the wiki

http://wiki.postgresql.org/wiki/Replication,_Clustering,_and_Connection_Pooling

it seems there are a few solutions that have now gained maturity. Something like rubyrep sounds ideal. It would have to
dealwith 
a) a flaky local connection
b) changing schemas (new tables, fields, views etc.) as well as data

Create/update/delete frequencies are reasonably low, generally individuals updating single records so of the order of
thousandsper day max. 

Any experiences/thoughts?

Oliver Kohll
www.gtwm.co.uk

-----BEGIN PGP SIGNED MESSAGE-----
Hash: RIPEMD160


> Is this a case for multi master do you think?
> I.e. running one on the internet, one locally.

Yes, could be.

> b) changing schemas (new tables, fields, views etc.) as well as data

That's a tall order; I don't think anything will do that automatically,
although rubyrep claims to at least pick up new tables.

> Any experiences/thoughts?

My experience is with Bucardo, which should do the job admirably
(but with the data only). My advice would be to just set up a test
system and try rubyrep and Bucardo out. For the latter, use the
latest Bucardo5 beta, as Bucardo4 will be deprecated soon:

http://bucardo.org/downloads/Bucardo-4.99.3.tar.gz

- --
Greg Sabino Mullane greg@turnstep.com
End Point Corporation http://www.endpoint.com/
PGP Key: 0x14964AC8 201201281026
http://biglumber.com/x/web?pk=2529DF6AB8F79407E94445B4BC9B906714964AC8
-----BEGIN PGP SIGNATURE-----

iEYEAREDAAYFAk8kE6gACgkQvJuQZxSWSshlVQCfXe2WdI58CRhKGIIF7mhfgNGb
hqAAn2tK1ALFwGwsspapzMKa3l728Sz4
=aYwt
-----END PGP SIGNATURE-----