[Zope-dev] Re: [Zope] PCGI?

[Jamie Heilman]

Chris Withers wrote:
> Don't think so, if you try and use the same port for two different Zope's 
> you get a 'Port in use' error on the one that started up second (on Linux, 
> anyway).

So you use a port map from the sound of it.  I think thats too error
prone and too ugly myself.  Consider, you've got 20 zope instances,
and 1 apache instance.  Your job as the admin is to maintain a
consistent configuration that encompasses the tethering of apache to
zope.  You can generate your configs using any number of scripting
utilities.  To figure out which port is 'free' you must now keep a
list of zope to port mappings, so when you add a new a new instance
you don't re-use a port.  Yes, you could strafe the port list in a
given range looking for one that already wasn't in use, but thats
going to fail badly when you hit a port that is temporarily down.
(who hasn't hit that dead modem in the hunt group at some point in
their life) A list is safer, but its cumbersome to maintain because
there's nothing inately ingrained about "port 8072" that makes one
think of bobs.example.com.  This is one of the things unix domain
sockets are better at.  You don't need a port map list if you know
that the socket for bobs.example.com will always appear at
/home/bobs/var/run/zope.sock.  Its much easier to script configuration
policies when the namespaces assure uniqueness and its much easier to
do hand configuration when a domain's resources have a human
recognisable property thats eases association.  Plus the cost of
maintaining a mapping list is much higher (especially given collision
and concurrency issues that arise with multiple admins, which you must
plan for) than simply using a schema which ensures uniqueness.  And
thats ignoring the various debates around firewalling practices as a
first line of defence, weak vs. strong ES models, etc.

Now all that said, I too think pcgi should just be dropped entirely
from zope.  It was an interesting idea, but unmaintained it does more
harm than good.

-- 
Jamie Heilman                   http://audible.transient.net/~jamie/
"We must be born with an intuition of mortality.  Before we know the words
 for it, before we know there are words, out we come bloodied and squalling
 with the knowledge that for all the compasses in the world, there's only
 one direction, and time is its only measure."		-Rosencrantz