What version of Foreman have you installed? First warning appears on call at 03-roles.rb on line 63 when it tries to create the role for external usergroups. I suppose it's because permissions define resource type as ExternalUsergroups instead of ExternalUsergroup (singular), this was present since Foreman 1.7 (introduced in #3976) and is ignored.

The error causing the task to fail is this

rake aborted!
TypeError: can't dup NilClass
/var/scratch/src/foreman/foreman/db/seeds.d/04-admin.rb:38:in `dup'
/var/scratch/src/foreman/foreman/db/seeds.d/04-admin.rb:38:in `block (2 levels) in <top (required)>'

As an easy workaround, set SEED_ADMIN_EMAIL variable to email address for your admin user and rerun the task, e.g.

SEED_ADMIN_EMAIL=admin@example.com bundle exec bin/rake db:seed

I can confirm this error, but the "error" in question should according to Dominic's note (http://projects.theforeman.org/issues/16204#note-1) not be treated as such.

My suggestion would be to look into omitting the backtrace, when it is a warning to not raise confusion about it being something to worry about.

Plus, an explanation why it is "ignorable" would make sense here as well, maybe.

Marek Hulán wrote:

As an easy workaround, set SEED_ADMIN_EMAIL variable to email address for your admin user and rerun the task, e.g.

I can confirm this works.