Rails breaks strangely on the deployment machine

I have a Rails application which runs just fine in both development
and production mode on the development system, which is Mac OS X. Not
Edge Rails, but the last release. However, when I deploy the app to
the production system, FreeBSD 6.1, AMD-64, I get consistent errors
on many of the controllers, but not all.

What happens is that ActionView seems to pass the wrong kind of
object to the views. Thus I get

undefined method `event_levels’ for #<#Class:0x18298c0:0x1829870>

and

td>
#{RAILS_ROOT}/app/views/admin/events/list.rhtml:16:in
_run_rhtml_admin_events_list' #{RAILS_ROOT}/app/views/admin/events/list.rhtml:12:ineach’
#{RAILS_ROOT}/app/views/admin/events/list.rhtml:12:in
_run_rhtml_admin_events_list' #{RAILS_ROOT}/app/controllers/admin/events_controller.rb:7:inindex’
/usr/local/lsws/fcgi-bin/RailsRunner.rb:12

Where the “Class” object in this case should be an Event. The same
thing goes for other types of objects, such as Payments. It is
completely consistent when it appears, it happens in both production
and development mode on the deployment system, but some of the
controllers/views do not seem to be affected at all.

It seems that it affects views which do explicit rendering using
shared templates, but it is not consistent. Some views break even if
they do not use any shared templates. It also seems to affect most of
the controllers located in a subfolder to app/controllers - /admin/ -
but again, not consistently so. (I remember reading somewhere that
there are problems with subfolders in the controller folder, but
again, some of the controllers work as they should.)

It should be pointed out that this does not happen with another app
deployed to the same FreeBSD machine. The malfunctioning app is the
newer one. The behaviour is the same under Webrick, Mongrel and
LiteSpeed.

I can see no recurring pattern at all. Any ideas before I start
tracing the internals of Rails?

/ Peter B.

Peter B. wrote:

I can see no recurring pattern at all. Any ideas before I start
tracing the internals of Rails?

Probably a dumb question, but are you sure you remembered to migrate
your database to the newest version on that installation?

–Al Evans