If you already used the VIP swap functionality in a cloud service, you quickly noticed that for the production slot you have a deterministic url in the format {cloudservicename}.cloudapp.net. For the staging slot, that is something totally different.
The problem: random generated name
You end up with a {auto-generated-guid}.cloudapp.net which makes it hard to give something usable to dev or testers since it will change again and again when you recreate a deployment in the staging slot. Azure will not help you there, they don't offer a way to have a deterministic DNS entry for the staging slot at the time of writing this article.
A solution: Use a CNAME dns entry
To avoid that problem, you can use a CNAME entry that point to {auto-generated-guid}.cloudapp.net. That way you can give your users a well known url that will never change. You will need to update your CNAME entry when you perform a new deployment to your staging slot though but this can be automated.
param(
[Parameter(Position=0,Mandatory=$true)]
[string]
$SubscriptionName,
[Parameter(Position=1,Mandatory=$true)]
[string]
$ServiceName
)
$ErrorActionPreference = 'Stop'
Select-AzureSubscription -SubscriptionName $SubscriptionName
$service = Get-AzureService -ServiceName $ServiceName
$deployment = $service | Get-AzureDeployment -Slot Staging
'Staging Url is: {0}' -f $deployment.Url
From that sample script you have access to the staging url via $deployment.Url, you can then use that value to update you DNS server.
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