- Always set the default boot selection to $saved_entry

- Always reset $saved_entry to the NOS boot selection.
  The purpose of this change is to make transitions to and from ONIE
  for update purposes more robust. Every boot selection to ONIE is
  automatically a boot-once choice.

packages/base/all/vendor-config-onl/src/python/onl/install/BaseInstall.py

@@ -419,8 +419,17 @@ terminal_input serial
 terminal_output serial
 set timeout=5
 
+# Always boot the saved_entry value
+load_env
+if [ "${saved_entry}" ] ; then
+   set default="${saved_entry}"
+fi
+
 menuentry %(boot_menu_entry)s {
   search --no-floppy --label --set=root ONL-BOOT
+  # Always return to this entry by default.
+  set saved_entry="0"
+  save_env saved_entry
   echo 'Loading %(boot_loading_name)s ...'
   insmod gzio
   insmod part_msdos
@@ -431,6 +440,9 @@ menuentry %(boot_menu_entry)s {
 # Menu entry to chainload ONIE
 menuentry ONIE {
   search --no-floppy --label --set=root ONIE-BOOT
+  # Always return to entry 0 by default.
+  set saved_entry="0"
+  save_env saved_entry
   echo 'Loading ONIE ...'
   chainloader +1
 }