サイトが表示されません。

上の掲示板をネット上に設置したのですが、ホーム画面は表示されるのですが、そこからクリックをして入ったら本来表示されるべきものが表示されません。クリックしたらこんなものが出てきます。

psycopg2.OperationalError
OperationalError: FATAL:  Peer authentication failed for user "simplech_role"
Traceback (most recent call last)
File "/root/simplechan/venv/lib/python2.7/site-packages/flask/app.py", line 2309, in __call__
return self.wsgi_app(environ, start_response)
File "/root/simplechan/venv/lib/python2.7/site-packages/flask/app.py", line 2295, in wsgi_app
response = self.handle_exception(e)
File "/root/simplechan/venv/lib/python2.7/site-packages/flask/app.py", line 1741, in handle_exception
reraise(exc_type, exc_value, tb)
File "/root/simplechan/venv/lib/python2.7/site-packages/flask/app.py", line 2292, in wsgi_app
response = self.full_dispatch_request()
File "/root/simplechan/venv/lib/python2.7/site-packages/flask/app.py", line 1815, in full_dispatch_request
rv = self.handle_user_exception(e)
File "/root/simplechan/venv/lib/python2.7/site-packages/flask/app.py", line 1718, in handle_user_exception
reraise(exc_type, exc_value, tb)
File "/root/simplechan/venv/lib/python2.7/site-packages/flask/app.py", line 1813, in full_dispatch_request
rv = self.dispatch_request()
File "/root/simplechan/venv/lib/python2.7/site-packages/flask/app.py", line 1799, in dispatch_request
return self.view_functions[rule.endpoint](**req.view_args)
File "/root/simplechan/app/app/__init__.py", line 91, in mod_logs
handler = Handler()
File "/root/simplechan/app/app/handler.py", line 26, in __init__
self.con = psycopg2.connect("dbname='{}' user='{}'".format(app.config['DB_NAME'], app.config['DB_ROLE']) )
File "/root/simplechan/venv/lib/python2.7/site-packages/psycopg2/__init__.py", line 130, in connect
conn = _connect(dsn, connection_factory=connection_factory, **kwasync)

OperationalError: FATAL: Peer authentication failed for user "simplech_role"

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と表示されます。何が原因でこういう風になったのでしょうか？
あと、サイトにもある通り"ffmpeg"をインストールしようと、activateしながら

pip install ffmpeg

と入力したら

Could not find a version that satisfies the requirement subprocess (from ffmpeg) (from versions: )
No matching distribution found for subprocess (from ffmpeg)

と赤文字で表示されました。どうやったら、インストールできますか？

あと、pythonを最後に実行したらこのように表示されます。

(venv) root@ubuntu-s-1vcpu-1gb-blr1-01:~/simplechan/app# python runserver.py
/root/simplechan/venv/local/lib/python2.7/site-packages/psycopg2/__init__.py:144: UserWarning: The psycopg2 wheel package will be renamed from release 2.8; in order to keep installing from binary please use "pip install psycopg2-binary" instead. For details see: <http://initd.org/psycopg/docs/install.html#binary-install-from-pypi>.
  """)
 * Serving Flask app "app" (lazy loading)
 * Environment: production
   WARNING: Do not use the development server in a production environment.
   Use a production WSGI server instead.
 * Debug mode: on
 * Running on http://0.0.0.0:5000/ (Press CTRL+C to quit)
 * Restarting with stat
/root/simplechan/venv/local/lib/python2.7/site-packages/psycopg2/__init__.py:144: UserWarning: The psycopg2 wheel package will be renamed from release 2.8; in order to keep installing from binary please use "pip install psycopg2-binary" instead. For details see: <http://initd.org/psycopg/docs/install.html#binary-install-from-pypi>.
  """)
 * Debugger is active!
 * Debugger PIN: 931-992-838