diff --git a/lib/objects.py b/lib/objects.py
index 6e7c33f39347bfcc781edd46c0706d40ba4df24f..3d0951725efb08d764f2c4d5d48cfbb8489c28bf 100644
--- a/lib/objects.py
+++ b/lib/objects.py
@@ -389,7 +389,7 @@ class ConfigData(ConfigObject):
 
 class NIC(ConfigObject):
   """Config object representing a network card."""
-  __slots__ = ["mac", "ip", "bridge", "nicparams"]
+  __slots__ = ["mac", "ip", "nicparams"]
 
   @classmethod
   def CheckParameterSyntax(cls, nicparams):
@@ -409,21 +409,6 @@ class NIC(ConfigObject):
       err = "Missing bridged nic link"
       raise errors.ConfigurationError(err)
 
-  def UpgradeConfig(self):
-    """Fill defaults for missing configuration values.
-
-    """
-    if self.nicparams is None:
-      self.nicparams = {}
-      if self.bridge is not None:
-        self.nicparams[constants.NIC_MODE] = constants.NIC_MODE_BRIDGED
-        self.nicparams[constants.NIC_LINK] = self.bridge
-    # bridge is no longer used it 2.1. The slot is left there to support
-    # upgrading, but can be removed once upgrades to the current version
-    # straight from 2.0 are deprecated.
-    if self.bridge is not None:
-      self.bridge = None
-
 
 class Disk(ConfigObject):
   """Config object representing a block device."""