Re: Yet another failure mode in pg_upgrade

On Sat, Sep  1, 2012 at 03:06:57PM -0400, Tom Lane wrote:
> Bruce Momjian <bruce@momjian.us> writes:
> > On Sat, Sep  1, 2012 at 02:43:35PM -0400, Tom Lane wrote:
> >> I'm inclined to think that the "no sockdir" case is broken and you
> >> should get rid of it.  If you're starting a postmaster, you can and
> >> should tell it a sockdir, period.  If you're running a live check this
> >> code is all moot anyway.
> 
> > I don't think you understand.  The "no sockdir" case is only for live
> > checks of pre-9.1 old servers, because we can't find the socket
> > directory being used.  Everything else uses the local directory for the
> > socket.  If we remove that case, we can't do live checks on pre-9.1
> > servers.
> 
> If it's a live check, then (a) you aren't restarting the postmaster,
> and (b) you wouldn't want to lock out TCP anyway.  So adding
> --listen-addresses to the string seems pointless and/or wrong.

What about the new server?  That is still started and stopped.  You are
right that this code is never going to be called for the check of a
running old server.

Let's walk through the options:

non-live check:uses current directory, start/stop old/new servers

live check, old server >= 9.1:only new server started/stopped, new server uses old server'ssocket directory and PGHOST
setso clients use the same directory
 

live check, old server < 9.1:only new server started/stopped, old/new servers use theirdefault/configured socket
directory

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com
 + It's impossible for everything to be true. +