diff --git a/mdb/api/serializers.py b/mdb/api/serializers.py
index eb5e7d7..5957bcc 100644
--- a/mdb/api/serializers.py
+++ b/mdb/api/serializers.py
@@ -1,7 +1,9 @@
-from mdb.models import Host
+from __future__ import unicode_literals
 from rest_framework import serializers
 from rest_framework.exceptions import ValidationError
 
+from mdb.models import Host
+
 
 class HostPXEValidateSerializer(serializers.Serializer):
     certname = serializers.CharField(required=True)
@@ -41,6 +43,7 @@ class HostPXEValidateSerializer(serializers.Serializer):
     def create(self, validated_data):
         # Make requests kind of idempotent by only allowing 1 request / installation
         self.host.pxe_installable = False
+        self.host.pxe_key = ''
         self.host.save()
 
         return self.host
diff --git a/mdb/signals.py b/mdb/signals.py
index b4f20e8..3a2018f 100644
--- a/mdb/signals.py
+++ b/mdb/signals.py
@@ -98,6 +98,7 @@ def create_pxe_key_and_write_pxe_files_when_host_changes(sender, instance, creat
     for pxe_file_name, pxe_file in host.as_pxe_files():
         path = os.path.join(settings.MDB_PXE_TFTP_ROOT, pxe_file_name)
         if host.pxe_installable:
+            # Write pxeconfig file to disk
             with open(path, 'w+') as f:
                 f.write(pxe_file)
                 logger.info("Created or updated {}".format(path))
@@ -120,6 +121,7 @@ def create_pxe_key_and_write_pxe_files_when_host_changes(sender, instance, creat
 
         else:
             if os.path.exists(path):
+                # Delete pxeconfig file from disk
                 os.unlink(path)
                 logger.info("deleted {}".format(path))