/simple-dns-forwarder

Primary LanguageDockerfile

Simple DNS forwarder for Azure VNET

This is a conatiner image of simple DNS forwarder, which works on Azure Container Instances, for Azure VNET.

Background

As this documentation describes, it is needed to use DNS forwarder in order that client PCs which connects to the VNET via ExpressRoute / P2S VPN and so on use Azure Private DNS Zone. This is because the Private DNS Zone can be used only for name resolution query from nodes in the VNET.

How to use

This image is based on distroless and contains only dnsmasq for forwarding DNS queries.

If you want to this on Azure Container Instances(ACI) in your Virtual Network, please take care the following points on deployment.

  • Container details in Basics
    This image is registered in GitHub Container Registry, so the following setting is needed.

    • Select Docker Hub or other registry for Image source
    • Select Public for Image type
    • Input ghcr.io/horihiro/simple-dns-forwarder:<tagName> as Image and replace <tagName> to a tag from the list
    • Select Linux for OS type

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  • Ports in Networking

    • Set VNET and subnet you want to deploy to
    • Set port 53 and UDP for DNS protocol
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  • Command override in Advanced
    Set following commands

    ["dnsmasq", "--no-daemon", "--server", "168.63.129.16"]

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After the deployment,

  1. Check the private IP address in General of the ACI
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  2. Set the private IP address to the DNS servers of the VNET you deployed ACI in
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