Can i re-create the config file from the destination folder

I had to erase all my server and can’t save my configuration file.
With my destination folder, can i take back or recreate a config file from it ?

If i re-create new one from stracht with same destination folder, same seed-phrase, etc., duplicati will auto-detect old versions points and re-sync it to just save news changes or it will be make a complete backup from zero ?

Unclear. Did you:

  • install a new system from scratch
  • restore an old image created with an image tool (such as Windows backup…)

If the former, you hardly can expect to do a new backup since all the data is in the Duplicati backend. It will be possible once you restore data from the Duplicati backend. In this case, recreate a backup configuration using all the good known parameters, recreate the database, and you should be able to restore data. When it’s done, backup should be good to start again.

If the latter, you should be extremely careful as the fact that there could be an old Duplicati configuration and old data could mean that you can destroy the up to date data on the backend. In this case you have first to remove the outdated Duplicati configuration from the image including especially the database before connecting the backend. Then proceed as above, recreate the database from the backend and restore the up to date data from the Duplicati backup.

I have installed a new system from scratch. But i not be able to save configuration file (crash). The source and backend are inchanged (same structural path) except minors files changed.
I would expect that i could be possible to generate a config file from the backend, bit it seems not.

if what you mean is the convenience of recreating the configuration from the backend, it’s not available by default, yes (there is an obscure feature of saving the configuration file with each backup, but nobody uses it as it’s more complicated than just save the config file manually).

But as of your second question in your initial post, the answer is clearly that it is NOT necessary to make a complete backup from zero. You can rebuild the database and continue the running backup (except that the logs are lost)

Thanks @gpatel-fr
It seems to work.
Rebuild a new backup configuration file from scratch with same parameters, then in “Advanced”/“Database”, i did “Repair” and after several minutes Duplicati found all my backup points.

You can browse the Restore tree if you like, to see if you set up the new backup the same way.
The COMPARE command in GUI Commandline can also help highlight unexpected config drift.
There’s no need to match configs. Old backups will remain as-is until versions get deleted later.