Cluster Frust

Michael Maass wrote:
As envisioned we (aka our team in Germany and me in Florida) did some testing, clustering WISE.

We encountered some difficulties we are presently not able to resolve due to a lack in understanding the WISE mechanics.


We set up a testing environment with

  • initialy two machines, Windows 2000 Client /2003 Server
  • WISE 1.2R2 classic (no Patches so far) and
  • ZEO in a version below 2.0.

Everything runs smooth until we try to upload (file)objects or images, aka everything that will not directly go into the data.fs.

Instead, a mechanism _wf_upload moves these assumed binary large objects (BLOBS) into the folder FileObjectStore, which it even generates if not present within the instance_home\var folder.

_wf_upload does not cross the client_storage-ZEO Path to the ZEO Server and the corresponding FileObjectStore.

After doing some homework I finaly conclude that BLOBs are just not handled by ZEO in the current version and that WISE does have a special routine (_wf_upload) to move them to the destination wise\var\FileObjectStore from which they are refered to by a corresponding statement in data.fs.

Aproach 1:

Set INSTANCE_HOME to the network share that is used by the ZEO (aka …wise\ on the ZEO Server Machine).
But, while the to configure the storage used, is read, the database mounted accordingly and the website can be run, the _wf_upload doesn´t go that road and ZOPE declares an error……http://server/fileobject/manage_object/_wf_upload starts with an underscore …… when trying to upload a File or an Image.

Several experiments with types of Mapping network drives, starting wise under different accounts to cater for a Network access problem did not solve the issue. _wf_upload works fine localy, the Network it ignores.

Trying to establish a symbolic link just to the FileObjectStore on the ZEO Server Machine fails due to the fact that Windows needs to be tricked to do so and junctions do not work across partitions.

Aproach 2:

As I write this I wonder if we could get Apache (of the Enterprise installation) to upload its Files to a network attached FileObjectUpload folder rather than the local one?

Whatever the procedure between Apache support to WISE for up- and download is should than be able to move the file into a FileObjectStore within the same folder ?!

After all it is just a question of how to synchronize File Object Stores between several WISE Servers or rather make them all use one on the Database Server. I admit to be a little stuck here and would very much appreciate some professional advice from the makers.

Maybe DFS Mirroring Folders could help the problem.

You might as well tell me to forget about it, because ZEO in ZOPE 2.10.x does take care of BLOB´s itself and that I should patiently wait for WISE 1.3 to rise.

However, from what I have been reading lately I know that the Issue has been recognized, weather it is going to be solved I could not find out.

So far so good.
I hope I´m not boaring you too much, but I had the Impression from earlyer exchanges, that clustering would be a desrired feature so I thought I´d bring the issue to your attention.


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