Listing 2 Run this when you're ready to bring everything back to normal

#!/bin/sh
#
# CONFIGURATION SECTION 
#     
# Set NDC to wherever the "ndc" binary is on your system
NDC=/usr/sbin/ndc
#    
# Set NAMEDB to the directory where you keep all your BIND records 
NAMEDB=/var/named
#    
# Set PRIMARYDB to the filename containing your "normal" DNS records
PRIMARYDB=db.foo.com
#    
# Set BACKUPDB to the filename containing your "fallback" DNS records 
BACKUPDB=bak.foo.com
#    
# END CONFIGURATION SECTION 
     
if [ ! -x $NDC ]; then 
   echo "File $NDC does not seem to exist or be executable. Please fix."
   exit 1  
fi   

if [ ! -x $NAMEDB ]; then 
   echo "Unable to access directory $NAMEDB. Please fix."
   exit 1  
fi   


cp $NAMEDB/$PRIMARYDB /tmp/$PRIMARYDB
cp $NAMEDB/$BACKUPDB $NAMEDB/$PRIMARYDB
cp /tmp/$PRIMARYDB $NAMEDB/$BACKUPDB
     
echo "Restarting BIND..."
$NDC restart