[Zope] Sharing of the same Data.fs on a separate machine

Martijn Pieters mj@digicool.com
Wed, 14 Jun 2000 11:16:56 +0200


On Wed, Jun 14, 2000 at 05:12:03PM +0800, Troy Tan Wee Teck wrote:
> Currently I have installed 2 machines(machine A and machine B) with Zope
> 2.1.6 and another machine called C which solely contain the Data.fs
> which is to be shared by the 2 machines. From what I know whatever
> changes to the Zope management it will update the Data.fs file (pls
> correct me if I am wrong).
> 
> The problem now is these 2 machines are supposed to be on all the time
> but whenever I did any changes to the Data.fs (example if I add in any
> dtml methods or whatever in the Zope management) using Machine A. I can
> only view the new changes that are being implemented on machine A, but
> when I switch to machine B to view those changes, strangely enough,
> machine B do not show me the changes that I have already done by machine
> A since both machine A and B are sharing the same Data.fs from machine
> C. However, if I do a reboot to machine B, then I will be able to able
> to view the changes that have been done.
> 
> What I would like to find out if there is a solution, to enable both
> machines to view any changes to the Zope management regardless of the
> Data.fs is modified by either machines.

Out of the box, Zope does not support sharing of one Data.fs amongst multiple
Zopes, the ZODB assumes it is the only process controlling the storage, an dit
in fact locks that storage. I am surprised you didn't run into more serious
trouble, if not at least a lock error, already.

If you wait a short period, then you can use ZEO, an extension to the ZODB
that let's you distribute one ZODB storage over multiple ZOpe installations,
precisely what you want. It is slated to be released Real Soon Now (TM). I
can't tell you when, because from my position I have no view whatsoever on
that project.

More information in ZEO:

  http://www.zope.org/Products/ZEO

-- 
Martijn Pieters
| Software Engineer    mailto:mj@digicool.com
| Digital Creations  http://www.digicool.com/
| Creators of Zope       http://www.zope.org/
|   The Open Source Web Application Server
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