<p>We are currently evaluating various Kubernetes aaS providers and Azure AKS was looking like a front runner. However, recently some information has emerged that the master and etcd nodes are not run in a HA configuration?</p>

<p>Is this correct? I find it hard to believe! There is nothing on their website with regard to the architecture of AKS which is always a worry but as they provide the master nodes as a service I don't understand how they would leave such a gaping hole?</p>

<p>Does any one have any more in depth information regarding the AKS architecture?</p>

<p>The worker nodes are in an Availability set meaning they are spread across update domains and fault domains.  In a service level agreement (SLA), the provider agrees to reimburse the customer for the cost of the service if the published service level isn't met. Since AKS itself is free, there is no cost available to reimburse and thus no formal SLA. However, AKS seeks to maintain availability of at least 99.5% for the Kubernetes API server. (<a href="https://learn.microsoft.com/en-us/azure/aks/faq#does-aks-offer-a-service-level-agreement" rel="nofollow noreferrer">source</a>)</p>
