diff --git a/interface/ri_tk_cmd.py b/interface/ri_tk_cmd.py
index 9e25d0d..0499ab1 100644
--- a/interface/ri_tk_cmd.py
+++ b/interface/ri_tk_cmd.py
@@ -313,11 +313,12 @@ devs  - raid component devices
 '''
     # all devs shall have same size. 
     unit=ri_data.Partition.unit
-    sz=999999999
+    dev_size_list=[]
     for p in ri_data.Partition.list:
         if p.device in devs:
-            if  float(p.size)< float(sz):
-                sz = float(p.size)
+            dev_size_list.append(float(p.size))
+    dev_size_list.sort()
+    sz=float(dev_size_list[0])
     if level == '0':
         sz=sz*len(devs)
         return str(sz)