Vagrant: Slow internet connection in guest

I'm trying to set up a vagrant. Host is Ubuntu 12.10. Here's my vagrant file:

Vagrant::Config.run do |config|

    config.vm.share_folder("v-root", "/vagrant", ".", :nfs => true)
    config.vm.network :bridged, :bridge => "eth0"

    config.vm.define "restserver" do |chefs_config|

        chefs_config.vm.box = "precise64"
        chefs_config.vm.box_url = "http://files.vagrantup.com/precise64.box"
        chefs_config.vm.host_name = "restserver"
        chefs_config.vm.network :hostonly, "192.168.20.50"
        chefs_config.vm.forward_port 80, 8080

        config.vm.provision :chef_solo do |chef|

            chef.log_level = :debug

            chef.cookbooks_path = "cookbooks"
            chef.run_list.clear

            chef.add_recipe "apt"
            chef.add_recipe "base"
            chef.add_recipe "mongodb::default"
            chef.add_recipe "nginx"
        end
    end
end

The problem is that my internet access from within the vagrant is terrible. It's very slow. I think the routing tables might be messed up. Here's the output from route -n:

Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         10.0.2.2        0.0.0.0         UG    0      0        0 eth0
0.0.0.0         10.0.2.2        0.0.0.0         UG    100    0        0 eth0
10.0.2.0        0.0.0.0         255.255.255.0   U     0      0        0 eth0
192.168.1.0     0.0.0.0         255.255.255.0   U     0      0        0 eth1
192.168.20.0    0.0.0.0         255.255.255.0   U     0      0        0 eth2

There are 2 routes to the default destination, although on the same NIC and to the same gateway. But perhaps this is causing an issue. At least that's what I thought but deleting the first default route doesn't help.

I need host-only networking so the nfs share will work. NAT is used for the port forwarding, and I've added the bridged network to try to give this guest access to the internet.

Has anyone any idea what's wrong? DNS is very slow to resolve, and it's slow to download anything from the internet.


Running Version 2 of the Vagrant config?

Sarah's provided the answer which is to use the NAT hosts DNS resolver as it's faster and will help speed things up.

However, in Version 2 of the vagrant config which is what most people are using now you'll have to do add following within your 'Vagrantfile' which will force the VM to uses NAT'd DNS:

config.vm.provider "virtualbox" do |v|
   v.customize ["modifyvm", :id, "--natdnshostresolver1", "on"]
   v.customize ["modifyvm", :id, "--natdnsproxy1", "on"]
end

You can tell if you're using v2 config if you have the following lines or something in the top of your Vagrantfile

VAGRANTFILE_API_VERSION = "2"
Vagrant.configure(VAGRANTFILE_API_VERSION) do |config|

Answer:

Add the following to the vagrant config:

config.vm.customize ["modifyvm", :id, "--natdnshostresolver1", "on"]

See here for more: Vagrant / VirtualBox DNS 10.0.2.3 not working