diff --git a/puppet/manifests/vagrant.pp b/puppet/manifests/vagrant.pp
index fb42e324a..9414a49de 100644
--- a/puppet/manifests/vagrant.pp
+++ b/puppet/manifests/vagrant.pp
@@ -34,6 +34,8 @@ line {"etc-hosts":
 
 file {"/etc/profile.d/treeherder.sh":
     content => "
+export DATABASE_URL='mysql://${DB_USER}:${DB_PASS}@localhost/treeherder'
+export DATABASE_URL_RO='mysql://${DB_USER}:${DB_PASS}@localhost/treeherder'
 export TREEHERDER_DEBUG='1'
 export TREEHERDER_DJANGO_SECRET_KEY='${DJANGO_SECRET_KEY}'
 "
diff --git a/treeherder/settings/base.py b/treeherder/settings/base.py
index f84d9ccf7..9b569315f 100644
--- a/treeherder/settings/base.py
+++ b/treeherder/settings/base.py
@@ -12,8 +12,6 @@ from treeherder import path
 
 # These settings can all be optionally set via env vars, or in local.py:
 
-DEFAULT_DATABASE_URL = 'mysql://treeherder_user:treeherder_pass@localhost/treeherder'
-
 TREEHERDER_MEMCACHED = os.environ.get("TREEHERDER_MEMCACHED", "127.0.0.1:11211")
 TREEHERDER_MEMCACHED_KEY_PREFIX = os.environ.get("TREEHERDER_MEMCACHED_KEY_PREFIX", "treeherder")
 
@@ -373,11 +371,11 @@ INSTALLED_APPS += LOCAL_APPS
 
 TEMPLATE_DEBUG = DEBUG
 
-# The default DB config is extracted from the DATABASE_URL environment variable, and the
-# read only config from DATABASE_URL_RO. If those are not set, DEFAULT_DATABASE_URL is used.
+# The database config is defined using environment variables of form:
+#   'mysql://username:password@host:optional_port/database_name'
 DATABASES = {
-    'default': dj_database_url.config(default=DEFAULT_DATABASE_URL),
-    'read_only': dj_database_url.config(env='DATABASE_URL_RO', default=DEFAULT_DATABASE_URL)
+    'default': dj_database_url.config(env='DATABASE_URL'),
+    'read_only': dj_database_url.config(env='DATABASE_URL_RO')
 }
 
 # Setup ssl connection for aws rds.