If you see the following output in /var/log/chef-manage/web/current and Chef Manage will not stay up when you start it with chef-manage-ctl start, this means you do not have the secrets in /etc/opscode/private-chef-secrets.json that are needed for Manage to communicate with a 14.x version of the Chef Server it is installed on
2022-06-15_19:40:47.03855 /opt/chef-manage/embedded/lib/ruby/gems/2.7.0/gems/veil-0.3.9/lib/veil/credential_collection/base.rb:77:in `get': Credential group 'manage' not found. (Veil::GroupNotFound)
2022-06-15_19:40:47.03860 from /opt/chef-manage/embedded/lib/ruby/gems/2.7.0/gems/veil-0.3.9/bin/veil-env-helper:70:in `block in <top (required)>'
To fix this, just reconfigure Chef Manage on the same machine with
Afterwards, you can check with PATH=/opt/opscode/embedded/bin:$PATH veil-dump-secrets /etc/opscode/private-chef-secrets.json | python -mjson.tool and you will see a section like this in the secrets file. This is what was missing earlier that Manage was complaining about in its log file above.