Re: SR/libpq - outbound interface/ipaddress binding

On Tue, 2010-02-23 at 10:00 +0100, Stefan Kaltenbrunner wrote:
> While playing with SR/HS in a more complex datacenter environment I
> immediatly hit the need to being able to specify the ipaddress(or
> interface) that the backend(or libpq) uses to connect to the master.
>
> There are a few reasons for being able to do so like:
>
> * we are now suddenly in a situation where the backend can create
> outbound connections on it's own so people will have to add firewall
> rules and being able to guarantee the source IP will help maintainance
> (otherwise stuff might break if you say add an alias IP on an interface)
> * prioritising - if you know that replication traffic is on a given IP
> you can actually do fancy stuff like routing it over a different gigE
> line or giving it prority on a WAN connection
> * some of those also apply to other libpq clients but those are usually
> not in that complex network/system environments as servers are

The whole reason for using libpq was that it gave us a stable base to
work on. It also means that we are restricted to any issues libpq has,
though the benefit is that any improvement there helps all clients. So
any changes you make would benefit Slony, Bucardo, Londiste as well.

Not for 9.0, though sounds like a welcome change.

--
Simon Riggs www.2ndQuadrant.com