Moving postgres db to central db server: build error

Installation
3

Hi Jay,

I followed the thread of Falco at Configure Discourse to use a separate PostgreSQL server The database server is available from the VM:

root@docker2:/var/discourse# pg_isready -d discourse -h 10.10.10.18 -p 5432 -U discourse    
10.10.10.18:5432 - Verbindungen werden angenommen

(connections are accepted)

The DB name, user and password in web_only.yml are also correct. The build error is

FAILED
--------------------
Pups::ExecError: cd /var/www/discourse && su discourse -c 'bundle exec rake db:migrate' failed with return #<Process:
:Status: pid 829 exit 1>
Location of failure: /usr/local/lib/ruby/gems/3.2.0/gems/pups-1.2.1/lib/pups/exec_command.rb:132:in `spawn'
exec failed with the params {"cd"=>"$home", "hook"=>"db_migrate", "cmd"=>["su discourse -c 'bundle exec rake db:migra
te'"]}
bootstrap failed with exit code 1

I am not a ruby expert, so I would need some help with the debugging starting from the error which appears here.

Bye, Thommie