On Tue, Aug 2, 2011 at 8:41 PM, Merlin Moncure <mmoncure@gmail.com> wrote:
> Basically this is formalizing good practice for failing over nodes and
> re-syncing to a promoted master. I will say though that one
> unfortunate side effect of using HS/SR for HA is that you need *four*
> servers to really protect yourself against data loss -- one master and
> three standbys. With a master and two standbys, you face a risk of
> significant loss if the promoted master dies while the remaining
> standby is syncing up to it. What you are looking for is a 'hot sync'
> so that standbys could be promoted in such a way that does not require
> a full sync -- that doesn't exist right now AFAIK.
repmgr is specifically designed to reduce the time for a "follow"
action to a very small amount.
There is no risk of significant loss.
--
Simon Riggs http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Training & Services