[ZODB-Dev] "Versions aren't supported" message in Plone 4 upgrade

[David Glick]

 On 9/9/10 3:28 PM, Mike Hammill wrote:
> David,
>
> I seem to recall from somewhere that using Data.fs was in some sense
> more complete, or more supported, or more something from some old
> migration guide, so I was shying away from doing an export/import.  Also
> there is the time involved in exporting/importing each site in the instance.
>
> However, I gave it a try.  When I did, I notice this text in 3.3.5:
>
> """
> Note: Zope can export/import objects in two dfferent formats: a binary
> format (called ZEXP) and as XML. The ZEXP format is the officially
> supported export/import format for moving data between identicial Zope
> installations (it is not a migration tool). The XML export/import is
> unsupported (and possibly broken under certain circumstances) - use it
> at your own risk.
> """
>
> It is the "it is not a migration tool" part plus that "identical" is
> underlined that worries me a bit.  In any case, the import into an empty
> 4.0.0 failed in my case with:
>
> """
> Site Error
>
> An error was encountered while publishing this resource.
>
> Error Type: ImportError
> Error Value: No module named LargePloneFolder
> """
>
> which I guess means (1) I have been using Plone too long :-) and (2) I
> have to find and somehow try to get rid of LargePloneFolder objects
> somehow before migrating??
>
> Thanks for the tip, though, maybe it will work if I can figure out how
> to proceed.  Perhaps I will be able to get to Plone 4 one of these days
> ;-)  I have be extremely strict about using any third-party add-ons,
> just so migration would go smoothly.  Looks like this time it is old
> Plone stuff itself that it getting in the way.  (BTW, we only use only
> one add-on: PloneFormGen.)
I meant that we exported the database under Plone 3.x and reimported to
a new database in the same Zope instance (still Plone 3.x with the same
versions of all software).  *Then* proceeded with a normal upgrade to
4.0 using the normal method and the new Data.fs.

David
----------		
David Glick
 Web Developer
 davidglick at groundwire.org
 206.286.1235x32

Groundwire: You Are Connected		
 http://groundwire.org