RHEL6: connectivity to a single IP Address may fail when arp is disabled and renabled for an interface.

Issue

• The following sequence of commands results in the a remote IP Address being inaccessible.
• ping hosta where hosta is another machine on the same subnet as ethX.
• ifconfig ethX -arp
• Now wait for the arp entry for hosta to expire.
  • arp -an
• Now ping hosta and it will timeout.
• Stop the ping and re-enable arp on ethX.
  • ifconfig ethX arp
• At this point hosta will remain inaccessible.
• It should be noted that alias interfaces like ethX:0 are also affected.