<p>We have different saas applications to deploy for our clients with 2 different configurations: some applications are exclusive to some clients (one or multiple apps for a single client) while others are shared between clients (same app for all clients but with different accounts). What's the best strategy (in terms of HA, security, etc.) to deploy them: using a big single mutual Kubernetes cluster for all of our clients or individual kubernetes cluster for each different client?</p>

MFM
<p>I'd say this is somewhat opinion based, but given you have <a href="https://kubernetes.io/docs/concepts/policy/resource-quotas/" rel="nofollow noreferrer">resource limits</a>, <a href="https://kubernetes.io/docs/concepts/services-networking/network-policies/" rel="nofollow noreferrer">network policies</a>, <a href="https://kubernetes.io/docs/concepts/overview/working-with-objects/namespaces/" rel="nofollow noreferrer">namespaces</a> and <a href="https://kubernetes.io/docs/reference/access-authn-authz/rbac/" rel="nofollow noreferrer">RBAC</a> you can use a single cluster for multiple clients.</p>

<p>You just have to make sure your cluster is resilient to failures if you have a single cluster for everything. For example, in <a href="https://azure.microsoft.com/en-us/updates/availability-zones-az-support-for-aks/" rel="nofollow noreferrer">AKS you can use availability zones</a></p>
