Troubleshooting DNS Resolution Issues in Vagrant/VirtualBox VMs: Fixing Specific Domain Resolution Failures


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When working with Vagrant and VirtualBox, you might encounter a peculiar situation where your VM can resolve some domains perfectly while failing on others. Here's what's happening under the hood:

$ dig security.ubuntu.com +short
91.189.92.181  # Works fine
$ dig us.archive.ubuntu.com
;; connection timed out  # Fails

VirtualBox uses a special NAT resolver (10.0.2.3) that sometimes struggles with certain DNS configurations. The key observations from our case:

  • Works: security.ubuntu.com, google.com, www.apple.com
  • Fails: us.archive.ubuntu.com, apple.com (without www)

The +trace output reveals the DNS resolution works when bypassing the local resolver, indicating the problem lies with VirtualBox's DNS proxy:

$ dig us.archive.ubuntu.com +trace
; Full trace shows successful resolution
; while standard query times out

Solution 1: Bypass VirtualBox DNS Proxy

Edit /etc/resolv.conf to use public DNS servers instead of 10.0.2.3:

nameserver 8.8.8.8
nameserver 8.8.4.4
options timeout:1 attempts:1

Solution 2: Modify Vagrantfile

Add this configuration to force proper DNS handling:

Vagrant.configure("2") do |config|
  config.vm.provider "virtualbox" do |vb|
    vb.customize ["modifyvm", :id, "--natdnshostresolver1", "on"]
    vb.customize ["modifyvm", :id, "--natdnsproxy1", "off"]
  end
end

To identify specific DNS issues:

# Check DNS response times
$ time dig @10.0.2.3 us.archive.ubuntu.com
$ time dig @8.8.8.8 us.archive.ubuntu.com

# Test different record types
$ dig us.archive.ubuntu.com A
$ dig us.archive.ubuntu.com AAAA
$ dig us.archive.ubuntu.com MX

For Ubuntu VMs, prevent resolv.conf from being overwritten:

$ sudo apt-get install resolvconf
$ sudo nano /etc/resolvconf/resolv.conf.d/head
# Add your preferred nameservers
$ sudo service resolvconf restart

Remember to test after each change:

$ ping -c 3 us.archive.ubuntu.com
$ curl -I http://us.archive.ubuntu.com

When working with Vagrant and VirtualBox, you might encounter a peculiar DNS resolution issue where some domains (like us.archive.ubuntu.com) fail to resolve while others (like security.ubuntu.com) work perfectly. The host machine resolves all domains correctly, but the VM struggles with specific ones.

The symptoms typically appear as:

Err http://us.archive.ubuntu.com/ubuntu/ lucid/main make 3.81-7ubuntu1
  Could not resolve 'us.archive.ubuntu.com'

Interestingly, dig with +trace works while normal queries fail:

vagrant@lucid64:~$ dig us.archive.ubuntu.com +trace
; <<>> DiG 9.7.0-P1 <<>> us.archive.ubuntu.com +trace
;; global options: +cmd
.           199183  IN  NS  d.root-servers.net.
[...]
us.archive.ubuntu.com.  600 IN  A   91.189.92.192

The issue stems from VirtualBox's NAT networking and DNS proxy behavior. The default /etc/resolv.conf shows:

nameserver 10.0.2.3
domain mydomain.com
search mydomain.com

VirtualBox's DNS proxy (10.0.2.3) sometimes struggles with certain DNS queries, particularly when:

  • The domain uses DNSSEC
  • There are specific TTL or record configurations
  • The response exceeds UDP packet size and needs TCP fallback

1. Bypass VirtualBox's DNS Proxy

Edit /etc/resolv.conf to use public DNS servers:

sudo bash -c 'cat > /etc/resolv.conf <

2. Configure Network Manager (For Ubuntu VMs)

sudo nano /etc/NetworkManager/NetworkManager.conf

Add or modify:

[main]
dns=default

Then restart NetworkManager:

sudo service network-manager restart

3. Vagrant-Specific Fix

Add this to your Vagrantfile:

config.vm.provision "shell", inline: <<-SHELL
  sudo resolvconf -u
  sudo systemctl restart systemd-resolved
SHELL

4. Testing DNS Resolution

Verify your changes with:

dig us.archive.ubuntu.com +short
dig @8.8.8.8 us.archive.ubuntu.com
ping -c 4 us.archive.ubuntu.com

If issues persist, check DNS query behavior:

tcpdump -i eth0 -n port 53
dig +dnssec us.archive.ubuntu.com
dig +tcp us.archive.ubuntu.com

For VirtualBox-specific debugging:

VBoxManage list hostonlyifs
VBoxManage modifyvm "VM name" --natdnshostresolver1 on

Consider these best practices:

  • Use bridged networking instead of NAT when possible
  • Keep VirtualBox Guest Additions updated
  • Regularly update your VM's DNS cache (sudo systemd-resolve --flush-caches)