diff --git a/plstackapi/core/models/key.py b/plstackapi/core/models/key.py
index 080f211..5174ebb 100644
--- a/plstackapi/core/models/key.py
+++ b/plstackapi/core/models/key.py
@@ -8,7 +8,7 @@
 
 class Key(PlCoreBase):
     name = models.CharField(max_length=256, unique=True)
-    key_id = models.CharField(max_length=256, unique=True, blank=True)
+    key_id = models.CharField(max_length=256, unique=True)
     key = models.CharField(max_length=512)
     type = models.CharField(max_length=256)
     blacklisted = models.BooleanField(default=False)
diff --git a/plstackapi/core/models/role.py b/plstackapi/core/models/role.py
index 3efa7a1..4b4b2e4 100644
--- a/plstackapi/core/models/role.py
+++ b/plstackapi/core/models/role.py
@@ -9,14 +9,13 @@
 class Role(PlCoreBase):
 
     #ROLE_CHOICES = (('admin', 'Admin'), ('pi', 'Principle Investigator'), ('user','User'))
-    role_id = models.CharField(max_length=256, unique=True, blank=True)
+    role_id = models.CharField(max_length=256, unique=True)
     role_type = models.CharField(max_length=80, unique=True)
 
     def __unicode__(self):  return u'%s' % (self.role_type)
 
 
     def save(self, *args, **kwds):
-
         driver = OpenStackDriver() 
         if not self.role_id:
             keystone_role = driver.create_role(name=self.role_type)
diff --git a/plstackapi/core/models/site.py b/plstackapi/core/models/site.py
index 2148e48..67257af 100644
--- a/plstackapi/core/models/site.py
+++ b/plstackapi/core/models/site.py
@@ -9,7 +9,7 @@
 
 class Site(PlCoreBase):
 
-    tenant_id = models.CharField(max_length=200, help_text="Keystone tenant id", blank=True)
+    tenant_id = models.CharField(max_length=200, help_text="Keystone tenant id")
     name = models.CharField(max_length=200, help_text="Name for this Site")
     site_url = models.URLField(null=True, blank=True, max_length=512, help_text="Site's Home URL Page")
     enabled = models.BooleanField(default=True, help_text="Status for this Site")
diff --git a/plstackapi/core/models/slice.py b/plstackapi/core/models/slice.py
index b080924..fe16402 100644
--- a/plstackapi/core/models/slice.py
+++ b/plstackapi/core/models/slice.py
@@ -10,7 +10,7 @@
 # Create your models here.
 
 class Slice(PlCoreBase):
-    tenant_id = models.CharField(max_length=200, help_text="Keystone tenant id", blank=True)
+    tenant_id = models.CharField(max_length=200, help_text="Keystone tenant id")
     name = models.CharField(unique=True, help_text="The Name of the Slice", max_length=80)
     enabled = models.BooleanField(default=True, help_text="Status for this Slice")
     SLICE_CHOICES = (('plc', 'PLC'), ('delegated', 'Delegated'), ('controller','Controller'), ('none','None'))
diff --git a/plstackapi/core/models/sliver.py b/plstackapi/core/models/sliver.py
index 1c4065f..27dda65 100644
--- a/plstackapi/core/models/sliver.py
+++ b/plstackapi/core/models/sliver.py
@@ -19,8 +19,26 @@
     key = models.ForeignKey(Key, related_name='slivers')
     slice = models.ForeignKey(Slice, related_name='slivers')
     node = models.ForeignKey(Node, related_name='slivers')
-    site = models.ForeignKey(Site, related_name='slivers')
+    #site = models.ForeignKey(Site, related_name='slivers')
     deploymentNetwork = models.ForeignKey(DeploymentNetwork, related_name='sliver_deploymentNetwork')
 
     def __unicode__(self):  return u'%s::%s' % (self.slice, self.deploymentNetwork)
 
+    def save(self, *args, **kwds):
+        driver = OpenStackDriver()
+        if not self.instance_id:
+            instance = driver.spawn_instance(name=self.name,
+                                   key_name = self.key.name,
+                                   flavor_id = self.flavor.flavor_id,
+                                   image_id = self.image.image_id,
+                                   hostname = self.node.name )
+            self.instance_id = instance.id
+
+        super(Sliver, self).save(*args, **kwds)
+
+    def delete(self, *args, **kwds):
+        driver = OpenStackDriver()
+        if self.instance_id:
+            driver.destroy_instance(self.instance_id)
+
+        super(Sliver, self).delete(*args, **kwds)
diff --git a/plstackapi/core/models/subnet.py b/plstackapi/core/models/subnet.py
index ae25b63..93a7ba5 100644
--- a/plstackapi/core/models/subnet.py
+++ b/plstackapi/core/models/subnet.py
@@ -8,7 +8,7 @@
 # Create your models here.
 
 class Subnet(PlCoreBase):
-    subnet_id = models.CharField(max_length=256, unique=True, blank=True)
+    subnet_id = models.CharField(max_length=256, unique=True)
     cidr = models.CharField(max_length=20)
     ip_version = models.IntegerField()
     start = models.IPAddressField()
diff --git a/plstackapi/core/models/user.py b/plstackapi/core/models/user.py
index c21601c..30bd2a9 100644
--- a/plstackapi/core/models/user.py
+++ b/plstackapi/core/models/user.py
@@ -9,7 +9,7 @@
 # Create your models here.
 
 class User(PlCoreBase):
-    user_id = models.CharField(max_length=256, unique=True, blank=True)
+    user_id = models.CharField(max_length=256, unique=True)
     firstname = models.CharField(help_text="person's given name", max_length=200)
     lastname = models.CharField(help_text="person's surname", max_length=200)
     email = models.EmailField(help_text="e-mail address", null=True)