fix: errors for drbd and lvm

ccnode/errors.py

@@ -58,6 +58,26 @@ class StorageVolumeError(StorageError):
     pass
 
 
+# lvm errors
+
+class LVMError(CCException):
+    '''
+    '''
+    pass
+
+# drbd errors
+
+class DRBDPoolError(CCException):
+    '''
+    '''
+    pass
+
+
+class DRBDError(CCException):
+    '''
+    '''
+    pass
+
 # job errors
 
 class JobManagerError(CCException):