typo
diff --git a/onos-build-base.py b/onos-build-base.py
index 4672fdf..2510d24 100755
--- a/onos-build-base.py
+++ b/onos-build-base.py
@@ -36,7 +36,7 @@
     assert 'disk image' in output
     return os.stat( vmdk )[ ST_SIZE ]
 
-def buildBaseVm( image, out, scriptFileName, scflavor='trusty64server', installMemory=4096, ovfMemory=4096  ):
+def buildBaseVm( image, out, scriptFileName, flavor='utopic64server', installMemory=4096, ovfMemory=4096  ):
     if not image:
         log( '* Error: no image specified' )
         sys.exit( 1 )
@@ -57,7 +57,7 @@
     parser = argparse.ArgumentParser( description='ONOS Base VM build script' )
     parser.add_argument( '-i', '--image', metavar='image', required=True,
                          help='Build from an existing VM image' )
-    parser.add_argument( '-f', '--flavor', default='trusty64server',
+    parser.add_argument( '-f', '--flavor', default='trusty64server', required=True,
                          help='VM flavor to build (e.g. trusty64server)' )
     parser.add_argument( 'scripts', nargs='*',
                          help='VM flavor(s) to build (e.g. trusty64server)' )
@@ -71,7 +71,7 @@
 
     print args
 
-    buildBaseVm( args.image, args.out, args.script )
+    buildBaseVm( args.image, args.out, args.script, flavor=args.flavor)
 
     if args.zip:
         log( '* Generating .zip file' )