Projects configuration and data missing after ST restart

[Pablo Accuosto]

Hi,

I am testing Vocbench-2.3 and using the ST version that comes with it (semanticturkey-0.11+vb-bundle-2.3.zip).

Today I was going to connect to VB and got an error message saying that the ST server was down, so I deleted the lock file and restarted it manually from the files in semanticturkey-0.11/bin - I run first./start and then ./st_server_run.

When I tried to log in again into VB, I got an error message saying that the project I was trying to load did not exist.

I created a new project and could log in ok - but could still not load my previous projects (which appear on VB).

I then went to the ST projects' directory 'SemanticTurkeyData/projects' and saw that there was only a directory for the newly created project, but not the ones that I had created before.

I copied the configurations of the new project with my previous projects' names and could then open them in VB - but they were now empty.

The projects were configured to use OpenRDF-Sesame as a remote triple store.
When I checked Sesame I saw that all the data from my previous projects was also missing.

I would like to know how to make sure that this doesn't happen again as we are planning to use Vocbench as our main taxonomy management solution.

Also - should the 'start' or 'st_run_server' scripts be invoked on reboot? Which is the best way to do it?

Is it possible that some of those scripts deleted the existing project's data or was it something else that could have happened?

Thanks,

Pablo

[Armando Stellato]

Dear Pablo,

that's the first thing I hear something like this. To recap some history, we had a bug in previous versions, for which some unusual errors could end up in the project being canceled. The only frequent one could be a missed connection to a remote server (frequent in that it could depend on the remote server being down which is a non-unfrequent event), for which the project was deleted. The bug originated from a wrong code going to another control which had to delete the project folder the first time it was created, in case of an error at project creation.
But this bug:
1) was present in older versions of Semantic Turkey, not the 0.11 (did you have this problem with a prior version and only after migrated to VB2.3/ST0.11 ?
2) it never did (there's no code performing such an action) any explicit data deletion, so it is not possible to have run any triple cleaning procedure on the remote server

I'll check onto it, but as I said, concerning the data deletion on the remote server, this sounds completely new to me. I'll check back onto the code, though I don't know of any part which should produce such a catastrophic event.

One thing that ma happen sometimes, is that, if you are using an in-memory repository (even if configured on the remote server) Sesame has not yet saved the data to mass storage (default should be every second...though...), but if your data is days old, this really looks strange to me. What was the configuration of your sesame repository on the remote server?

To reply to your specific questions on this and other email:

1) the st_run_server is the one to run, though I think it is just a copy of the "start" one.
2) there is no specific procedure on reboot other than rerunning the server with those scripts

Cheers,

Armando

> -----Messaggio originale-----
> Da: semantict...@googlegroups.com [mailto:semanticturkey-
> us...@googlegroups.com] Per conto di Pablo Accuosto
> Inviato: venerdì 28 agosto 2015 19:22
> A: semanticturkey-user <semantict...@googlegroups.com>
> Oggetto: [semanticturkey-user] Projects configuration and data missing after
> ST restart

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[Pablo Accuosto]

Dear Armando,

Thank you very much for your response.

I was already running the 0.11 version of ST.

But I was now wondering if the error could have originated in the server, actually.

I am running the openrdf-sesame.war version that comes in the graphdb-lite-6.1.8410 package.

There are reports of bugs in previous versions of GraphDB-Lite where the data was erased after a Tomcat restart - it's supposed to be fixed now, but I don't know...

I am working with a repository of type OWLIM-Lite with "No Persistence = False".

Is it possible that the ST server deleted the project files if it couldn't find the data in the triple store? (The repository still existed but maybe the Schemas and Concepts data didn't - I didn't check before restarting ST).

Thanks a lot!

Pablo

[Armando Stellato]

Hi Pablo,

 

I can’t say about the specific OWLIM-Lite instance, but as I said in the previous email, I don’t know of any portion of code which should delete a project if no data is found in the sesame server.

Anyway, for remote projects, this is not a big issue, you can:

 

1)      Just recreate the project from the Semantic Turkey client (obvioulsyl reuse the same name and same settings)

2)      You can backup just once the project (if it is a remote connection, there is no data, nor history in the project, unless you import other ontologies) and then reinstall it by just copying it into the projects folder as is

 

Cheers,

Armando