diff --git a/lib/puppet/file_bucket/dipper.rb b/lib/puppet/file_bucket/dipper.rb
index b012a8681..f4bef28a8 100644
--- a/lib/puppet/file_bucket/dipper.rb
+++ b/lib/puppet/file_bucket/dipper.rb
@@ -1,99 +1,104 @@
 require 'puppet/file_bucket'
 require 'puppet/file_bucket/file'
 require 'puppet/indirector/request'
 
 class Puppet::FileBucket::Dipper
   # This is a transitional implementation that uses REST
   # to access remote filebucket files.
 
   attr_accessor :name
 
   # Create our bucket client
   def initialize(hash = {})
     # Emulate the XMLRPC client
     server      = hash[:Server]
     port        = hash[:Port] || Puppet[:masterport]
     environment = Puppet[:environment]
 
     if hash.include?(:Path)
       @local_path = hash[:Path]
       @rest_path  = nil
     else
       @local_path = nil
       @rest_path = "https://#{server}:#{port}/#{environment}/file_bucket_file/"
     end
   end
 
   def local?
     !! @local_path
   end
 
   # Back up a file to our bucket
   def backup(file)
     raise(ArgumentError, "File #{file} does not exist") unless ::File.exist?(file)
     contents = ::File.read(file)
     begin
       file_bucket_file = Puppet::FileBucket::File.new(contents, :bucket_path => @local_path)
       dest_path = "#{@rest_path}#{file_bucket_file.name}"
 
-      file_bucket_file.save(dest_path)
+      # Make a HEAD request for the file so that we don't waste time
+      # uploading it if it already exists in the bucket.
+      unless Puppet::FileBucket::File.head("#{@rest_path}#{file_bucket_file.checksum_type}/#{file_bucket_file.checksum_data}")
+        file_bucket_file.save(dest_path)
+      end
+
       return file_bucket_file.checksum_data
     rescue => detail
       puts detail.backtrace if Puppet[:trace]
       raise Puppet::Error, "Could not back up #{file}: #{detail}"
     end
   end
 
   # Retrieve a file by sum.
   def getfile(sum)
     source_path = "#{@rest_path}md5/#{sum}"
     file_bucket_file = Puppet::FileBucket::File.find(source_path, :bucket_path => @local_path)
 
     raise Puppet::Error, "File not found" unless file_bucket_file
     file_bucket_file.to_s
   end
 
   # Restore the file
   def restore(file,sum)
     restore = true
     if FileTest.exists?(file)
       cursum = Digest::MD5.hexdigest(::File.read(file))
 
       # if the checksum has changed...
       # this might be extra effort
       if cursum == sum
         restore = false
       end
     end
 
     if restore
       if newcontents = getfile(sum)
         tmp = ""
         newsum = Digest::MD5.hexdigest(newcontents)
         changed = nil
         if FileTest.exists?(file) and ! FileTest.writable?(file)
           changed = ::File.stat(file).mode
           ::File.chmod(changed | 0200, file)
         end
         ::File.open(file, ::File::WRONLY|::File::TRUNC|::File::CREAT) { |of|
           of.print(newcontents)
         }
         ::File.chmod(changed, file) if changed
       else
         Puppet.err "Could not find file with checksum #{sum}"
         return nil
       end
       return newsum
     else
       return nil
     end
   end
 
   private
   def absolutize_path( path )
     require 'pathname'
     Pathname.new(path).realpath
   end
 
 end
 
diff --git a/spec/unit/file_bucket/dipper_spec.rb b/spec/unit/file_bucket/dipper_spec.rb
index 730e10792..3e9e8b145 100755
--- a/spec/unit/file_bucket/dipper_spec.rb
+++ b/spec/unit/file_bucket/dipper_spec.rb
@@ -1,72 +1,95 @@
 #!/usr/bin/env ruby
 
 require File.dirname(__FILE__) + '/../../spec_helper'
 
 require 'pathname'
 
 require 'puppet/file_bucket/dipper'
 describe Puppet::FileBucket::Dipper do
   include PuppetSpec::Files
 
   def make_tmp_file(contents)
     file = tmpfile("file_bucket_file")
     File.open(file, 'w') { |f| f.write(contents) }
     file
   end
 
+  it "should fail in an informative way when there are failures checking for the file on the server" do
+    @dipper = Puppet::FileBucket::Dipper.new(:Path => "/my/bucket")
+
+    file = make_tmp_file('contents')
+    Puppet::FileBucket::File.expects(:head).raises ArgumentError
+
+    lambda { @dipper.backup(file) }.should raise_error(Puppet::Error)
+  end
+
   it "should fail in an informative way when there are failures backing up to the server" do
     @dipper = Puppet::FileBucket::Dipper.new(:Path => "/my/bucket")
 
     file = make_tmp_file('contents')
+    Puppet::FileBucket::File.expects(:head).returns false
     Puppet::FileBucket::File.any_instance.expects(:save).raises ArgumentError
 
     lambda { @dipper.backup(file) }.should raise_error(Puppet::Error)
   end
 
   it "should backup files to a local bucket" do
     @dipper = Puppet::FileBucket::Dipper.new(:Path => "/my/bucket")
 
     file = make_tmp_file('my contents')
     checksum = Digest::MD5.hexdigest('my contents')
 
+    Puppet::FileBucket::File.expects(:head).returns false
     Puppet::FileBucket::File.any_instance.expects(:save)
     @dipper.backup(file).should == checksum
   end
 
+  it "should not backup a file that is already in the bucket" do
+    @dipper = Puppet::FileBucket::Dipper.new(:Path => "/my/bucket")
+
+    file = make_tmp_file('my contents')
+    checksum = Digest::MD5.hexdigest('my contents')
+
+    Puppet::FileBucket::File.expects(:head).returns true
+    Puppet::FileBucket::File.any_instance.expects(:save).never
+    @dipper.backup(file).should == checksum
+  end
+
   it "should retrieve files from a local bucket" do
     @dipper = Puppet::FileBucket::Dipper.new(:Path => "/my/bucket")
 
     checksum = Digest::MD5.hexdigest('my contents')
 
     Puppet::FileBucket::File.expects(:find).with{|x,opts|
       x == "md5/#{checksum}"
     }.returns(Puppet::FileBucket::File.new('my contents'))
 
     @dipper.getfile(checksum).should == 'my contents'
   end
 
   it "should backup files to a remote server" do
     @dipper = Puppet::FileBucket::Dipper.new(:Server => "puppetmaster", :Port => "31337")
 
     file = make_tmp_file('my contents')
     checksum = Digest::MD5.hexdigest('my contents')
 
     real_path = Pathname.new(file).realpath
 
+    Puppet::FileBucket::File.expects(:head).with("https://puppetmaster:31337/production/file_bucket_file/md5/#{checksum}").returns false
     Puppet::FileBucket::File.any_instance.expects(:save).with("https://puppetmaster:31337/production/file_bucket_file/md5/#{checksum}")
 
     @dipper.backup(file).should == checksum
   end
 
   it "should retrieve files from a remote server" do
     @dipper = Puppet::FileBucket::Dipper.new(:Server => "puppetmaster", :Port => "31337")
 
     checksum = Digest::MD5.hexdigest('my contents')
 
     Puppet::FileBucket::File.expects(:find).with{|x,opts|
       x == "https://puppetmaster:31337/production/file_bucket_file/md5/#{checksum}"
     }.returns(Puppet::FileBucket::File.new('my contents'))
 
     @dipper.getfile(checksum).should == "my contents"
   end
 end