vm.install-*: workaround for spurious "No network interfaces detected"

slapos/recipe/vm.py

@@ -101,6 +101,10 @@ class BaseRecipe(EnvironMixin):
 class InstallDebianRecipe(BaseRecipe):
 
   preseed = """
+    # Workaround for spurious "No network interfaces detected"
+    # See https://bugs.debian.org/842201
+    fb = false
+
     auto = true
     priority = critical
     partman/choose_partition = finish
@@ -153,7 +157,7 @@ class InstallDebianRecipe(BaseRecipe):
     cmdline = {}
     for preseed in self.preseed.splitlines():
       preseed = preseed.strip()
-      if preseed:
+      if preseed and preseed[0] != '#':
         k, v = preseed.split('=', 1)
         cmdline[k.strip()] = v.strip()
     for k, v in options.iteritems():