Internal Static IP on VM in a Virtual Network from Windows Azure

In general I don’t discuss about IT PRO features from Windows Azure, but some of them are very important. Why: because in the end we design solution to run somewhere. In today post we will talk about how static IP on VM from Windows Azure.
I assume that this is the first time when you hear about this subject. Let’s start with the begging. On Azure we have a Virtual Network where we can add our VM. Of course each machine from this network will have an IP based on the Virtual Network configuration (subnet range, available IPs in our Virtual Network and so on).
When we restart of machine (OS upgrades, application upgrades, …) the IP allocated to the machine will remain the same. If we deallocate one of VM machines from Virtual Network, the IP will be automatically available to other new VM that will be added. This means that if we have a machine with 192.168.1.2 (internal IP) and we deallocate it, the next VM that will be added to the network will have this IP, even if there will be other IP’s available in our network.
Unfortunately, if we deallocate our machine the machine and recreate it, the IP that is allocate to it will not be the same (if other VM were already added to the network or an IP with smaller value is available). Because of this, if we configure other VM to connect to a specific IP, we will have problems with machines IP – we will need to change the configuration of the VM that tries to connect to a resource using the IP (sticky connection).
First of all we should access the machines based on the name and not based on IP, but there are times when we cannot use the name of the machine. A new feature was added to Windows Azure that give us the possibility to configure the internal IP of a VM that is created on our private network.
This mean that when you create the VM you can specify what the internal IP will be. Unfortunately this cannot be made from Windows Azure portal (yet, in the future we may have this option available).
We can configure the internal IP using power shell scripts. In the setup of our VM we have a new configuration called “Set-AzureStaticVNetIP”. This will allow us to set the internal IP

Set-AzureStaticVNetIP -IPAddress 192.168.1.2

To get the IP of the machine we can use the following command

Get-AzureStaticVNetIP -VM {VirtualMchine}

To remove the internal static IP you need to use the following command “Remove-AzureStaticVNetIP”
Enjoy!