Suppress 'Network down' warnings when link_master_slave feature is on

Ticket: CM-4462
Reviewed By:
Testing Done: Tested with interfaces file given in the bug.

The 'network down' msg from the kernel is when the lower device is not
'admin up'. In CM-4462 it is seen when the vlan interface on the bond
is 'admin up' when the bond is still in 'admin down' state.
The bond is also a bridge port so, bond will be 'admin up' when
the bridge it belongs to is brought up.

As link_master_slave feature is on only when all network interfaces
are brought up/down, the states of all interfaces will eventually
converge to 'admin up', so ignoring such transient 'network down' messages.

ifupdown/ifupdownmain.py

@@ -236,6 +236,21 @@ class ifupdownMain(ifupdownBase):
         else:
             self._link_master_slave = False
 
+    def link_master_slave_ignore_error(self, errorstr):
+        # If link master slave flag is set, 
+        # there may be cases where the lowerdev may not be
+        # up resulting in 'Network is down' error
+        # This can happen if the lowerdev is a LINK_SLAVE
+        # of another interface which is not up yet
+        # example of such a case:
+        #   bringing up a vlan on a bond interface and the bond
+        #   is a LINK_SLAVE of a bridge (in other words the bond is
+        #   part of a bridge) which is not up yet
+        if self._link_master_slave:
+           if 'Network is down':
+              return True
+        return False
+
     def get_ifaceobjs(self, ifacename):
         return self.ifaceobjdict.get(ifacename)
 

ifupdown/scheduler.py

@@ -136,6 +136,7 @@ class ifaceScheduler():
                 try:
                     handler(ifupdownobj, ifaceobjs[0])
                 except Exception, e:
+                    if not ifupdownobj.link_master_slave_ignore_error(str(e)):
                        ifupdownobj.logger.warn('%s: %s'
                                    %(ifaceobjs[0].name, str(e)))
                     pass