noelbundick · September 19, 2019 15:20 · Sep 19, 2019
diff --git a/README.md b/README.md
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+Some quick thoughts on using many Azure subscriptions vs many resource groups in one subscription
+
+* Limits are applied at the subscription (+ sometimes region) level. If one RG uses 500 cores, other business units may be blocked until you open a support request.
+* Preview features are applied at the subscription level - other RG's can't opt-in/out. Ex: if you wanted to use the AKS + VMSS preview, you need to be sure that all teams want (and can support) the feature
+* This is really hit & miss, but there are some actions that can't be performed based on other resources being present in the same subscription
+
+https://docs.microsoft.com/bs-latn-ba/azure/storage/common/storage-auth-aad-rbac-portal
+
+```
+If your subscription includes an Azure DataBricks namespace, roles assigned at the subscription scope will be blocked from granting access to blob and queue data.
+```
+
+* Azure Cost Management works across both Subscriptions & Resource Groups (and Management Groups!)
+* You can apply RBAC across subscriptions (if they are in the same AAD tenant) to grant read-only, "attach to VNET", etc. So it's not an either/or scenario
+* The management challenge is present in both approaches - you still want to figure out how to define & manage N groups. Your scripts/tools might change, but the concepts are the same