Configuring IP and DNS addresses in Microsoft Azure

I recently started testing Microsoft Azure. One of the first things I did was the deployment of a virtual machine. Somehow I missed the section to configure the DNS servers in the defined virtual network. It looked useful to write some of my findings.

I use the Microsoft Azure Portal, which is currently in Preview (Beta phase).

AZURE-IPandDNS1

IP addresses can be assigned in three different ways.

  1. By default, a virtual machine within Microsoft Azure will receive a Dynamic IP address.
  2. Within the Azure Portal you have the ability to define a static IP address. However these static IP addresses are assigned by using a DHCP and IP address reservations.
  3. Last but not least, you still have the ability to define a custom IP address from within the guest operating system. However, I have a hunch this can cause some troubles with out-of-band-management (“Azure Portal > VM > Connect“) as the Azure platform is not aware of the network configuration configured within the virtual machine. (I should add this to my todo list…)

The IP address configuration within Azure can be defined in the Virtual Machine settings (“Browse > Virtual Machines > MyVM > Settings > IP addresses“).

DNS servers on the other side are configured by using the Virtual Network (“Browse > Virtual Network > MyVirtualNetwork > DNS servers“). The DNS addresses within the same subnet tend to be the same as usual, so it’s kinda logical they put it over there.

  1. By default, the DNS servers are configured by using DHCP. In case a custom DNS has been configured, DHCP will still be used to configure the virtual machine. In case no DNS has been configured, the Microsoft DNS server(s) will be used. The Microsoft Azure DNS configured by DHCP was ‘168.63.129.16’ during my tests.
  2. Additionally, the DNS server can be configured within the virtual machine which is once again not advised to my own opinion.

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Thanks for reading!

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