Hello,

I am trying to upgrade from OpenProject 7.4 to 8 and the first step is making a backup.

When I run 

sudo openproject run backup

I get an error: 

* Generating database backup.../opt/openproject/vendor/ruby-2.4.4/lib/ruby/2.4.0/uri/common.rb:739:in `URI': bad argument (expected URI object or URI string) (ArgumentError)        from -e:1:in `<main>'

I looked in the backup script  (/opt/openproject/packaging/scripts/backup) and noticed that the DATABASE_URL is used, but apparently there is no such variable. 

Running 

sudo openproject config:get DATABASE_URL

returns no result.

How and where should I set this variable?