Comment 2 for bug 1269921

The root cause is in /etc/networking/if-pre-up.d/ifenslave. In starting at line 260.

if the /etc/run/network/ifenslave.<BOND> file doesn't exist ifup goes into an unterminated while loop, since there is nothing inside the loop that will create the file.

 [ ! -f /run/network/ifenslave.$BOND_MASTER ] && echo "Waiting for bond master $BOND_MASTER to be ready"
 while :; do
  if [ -f /run/network/ifenslave.$BOND_MASTER ]; then
   break
  fi
  sleep 0.1
 done