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

[Mike Hammill]

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.)

/Mike

On 09/09/2010 04:25 PM, David Glick wrote:
> Mike, we successfully upgraded an old Plone site whose database
> contained ZODB versions by ZEXP-exporting the entire thing, then
> reimporting into a fresh database.
> 
> David
> ----------		
> David Glick
>  Web Developer
>  davidglick at groundwire.org
>  206.286.1235x32
> 
> Groundwire: You Are Connected		
>  http://groundwire.org