Re: Enterprise readiness - mirroring / incremental backup solutions?

On Tue, Nov 19, 2002 at 11:42:30AM +0000, Kieran wrote:
> 3. Fast (i.e. < 5 mins) failover time to a constantly mirrored secondary
> database server.

We currently do this with the commercial version of rserv; it's
available from PostgreSQL, Inc. They're working on making it a
little less hairy to use; but even though it is a little awkward, it
works for us, and I suspect would handle your problem.

> 4. Ability to perform continous network backups such that in the event
> of both the primary database server and mirrored database server
> suffering total failure, no more than 1 hour of data is lost.

I'd do this with multiple mirrors. eRServer supports multiple
slaves. Point-in-time recovery, which is I guess what you want, is
high on our list of desired features, too, and I gather it will be in
7.4.

> I'd imagine it may be possible to satisfy 3. using file system level
> mirroring, but I'd appreciate it if someone could confirm this.

As I understand it, this is pretty risky.

> My last question is somewhat pie-in-the sky, but assuming that
> PostgreSQL cannot currently meet requirements 3 & 4 even with 3rd party
> solutions, what are people's gut reactions to whether a small team (e.g.
> 5-6) of experienced, full-time paid developers could add mirroring and
> incremental backup support to PostgreSQL within 18 months?

I have heard reasonably well-informed estimates that the multi-master
replication system could be completed in 18 months by a sufficiently
familiar developer. You'll probably want to look to the replication
project list for more details.

A

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