Re: Replication

On Thu, 2007-06-14 at 16:14 -0700, Craig James wrote:
> Looking for replication solutions, I find:
>
> Slony-I
>  Seems good, single master only, master is a single point of failure,
>  no good failover system for electing a new master or having a failed
>  master rejoin the cluster.  Slave databases are mostly for safety or
>  for parallelizing queries for performance.  Suffers from O(N^2)
>  communications (N = cluster size).
>

There's MOVE SET which transfers the origin (master) from one node to
another without losing any committed transactions.

There's also FAILOVER, which can set a new origin even if the old origin
is completely gone, however you will lose the transactions that haven't
been replicated yet.

To have a new node join the cluster, you SUBSCRIBE SET, and you can MOVE
SET to it later if you want that to be the master.

Regards,
    Jeff Davis