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Your LimeSurvey version: 3.27.22
Own server or LimeSurvey hosting: own server
Survey theme/template:
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Good morning everyone, 

we have a production server with LimeSurvey 3 (full of real users, completed surveys, etc.) and we would like to upgrade it to version 6.

We need advice on what is the best way to do this:

• A ) upgrade the production server from 3 to 6   (maybe following:  manual.limesurvey.org/Upgrading_from_a_previous_version )
  
• B ) use another server where  there is already version 6 (empty, no real users, no surveys) and then migrate the database from 3 there?   Is this possible?

What is the best, fastest and least problematic way?

Thank you very much

There are upsides and downsides to both approaches.

I personally am a fan of running different versions of Limesurvey in parallel for a while and gradually move everything to the newer installation, but I also don't have a lot of users on my installations, which makes things easier.

If you have custom survey themes or a lot of workarounds in your surveys or a lot of surveys running continuously, gradually moving to a different installation that runs in parallel might be the way to go. However, this might mean that at the time when you copy the database to install the new version with it as a base you will have changes in the old one and then there will be changes in the new one and the databases will move away from each other.

But the advantages are that you can test thoroughly if everything works, there shouldn't be any major problems in production, as old surveys run on the old installation until they are done, new surveys will be built on the new version.

Disadvantages: With continuous surveys, you will have a cut at one point, because the survey URL will have to change.

But in case I wouldn't install version 6 first and then migrate the database, but rather create a copy of the old database and install version 6 using this copy.

holch wrote:

But in case I wouldn't install version 6 first and then migrate the database, but rather create a copy of the old database and install version 6 using this copy.
 

general advice : backup , backup and backup again ! And test your backup !

general advice : backup , backup and backup again ! And test your backup !

Of course! This is the most essential point. Actually shouldn't be necessary to mention. But we have seen it all.

holch wrote:

general advice : backup , backup and backup again ! And test your backup !

Of course! This is the most essential point. Actually shouldn't be necessary to mention. But we have seen it all.
 

I can testify that you absolutely must test your backups regularly. I lost my personal Gnu Social after 12 years of good service.

If you have custom survey themes or a lot of workarounds in your surveys or a lot of surveys running continuously, gradually moving to a different installation that runs in parallel might be the way to go. However, this might mean that at the time when you copy the database to install the new version with it as a base you will have changes in the old one and then there will be changes in the new one and the databases will move away from each other.