Re: Ability to listen on two unix sockets

On Wed, Jun 06, 2012 at 11:32:45AM -0400, Tom Lane wrote:
> I had forgotten that conversation, but it does seem like there is
> interest in this type of configuration. Can anybody confirm that
> dropping a socket into a chroot or jail would actually work, ie
> make it possible to connect from inside the chroot to a postmaster
> running outside? If that's real and not just wishful thinking,
> it seems like enough of an argument to justify supporting N sockets.

We need to deal with exactly this sort of issue with schroot, where
we may want to provide programs in the chroot with access to
facilities outside the chroot. We generally just bind mount in the
minimal set of stuff needed. This might mean binding just the socket,
or it could be /var/run/postgresql. We do this for the X11 socket
for our desktop configuration profile to permit X11 programs to run
in a chroot, though we currently bind mount all of /tmp rather than
just the socket, since we want that as well in any case.

(http://people.debian.org/~rleigh/schroot.pdf)

While not exactly what was proposed (multiple sockets), this allows
one to re-use a single socket without the daemon requiring any
special support for it.

Regards,
Roger

--
.''`. Roger Leigh
: :' : Debian GNU/Linux http://people.debian.org/~rleigh/
`. `' schroot and sbuild http://alioth.debian.org/projects/buildd-tools
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