@spottedmahn Managed Identity can not be used just for 1 log analytic workspace, It has to be a Log Analytics cluster.
The screenshot if is mostly of a similar cluster which include multiple containers.
You would need to create the log analytic cluster and associate Log analytics workspace to it. (https://learn.microsoft.com/en-us/azure/active-directory/managed-identities-azure-resources/services-support-managed-identities#azure-log-analytics-cluster)
Here is how you can create it : https://learn.microsoft.com/en-us/azure/azure-monitor/logs/logs-dedicated-clusters#create-a-dedicated-cluster
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