I recently had some cases where I lost the public IP address which was assigned to a cloud service within Windows Azure. This was not really a desired scenario because these IP addresses were already used and registered in DNS. The use of a CNAME to *.cloudapp.net was not an option because the use of certificates.
The reason why I lost the public IP address on these services was because of the state of the Virtual Machines within the services. Because of the changes of the billing mechanism in Windows Azure (June, 2013), there was a new status introduced for the Virtual Machines. The new status: Stopped (Deallocated) places the VM in a special state which means that the configuration of the VM is not actively being associated with fabric resources. This results in the fact that you are not being billed for the hourly compute time while the VM is in that state. This is of course a very useful feature, however when all of your VM’s in a Cloud Service are put in this state, the public IP address associated with that service will be released. The next time you start a VM in the Cloud Service it will …read more
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