Hello @Karsten Leonhardt ,
I understand that you are trying to create a private endpoint to your private aks cluster with static ip address configuration but getting a BadRequest error with code PrivateEndpointWithIpConfigurationsCannotHaveGroupIdsOrMemberNames.
I checked with the Azure Private Endpoint Product Group team and below is the update:
Static IP for Private Endpoint is not supported for a few services like Application gateway, AKS and HDI. We are working on the fix and hoping it can be rolled out quickly. As of now, we don't have an ETA on this fix.
In the meantime, we will update the documentation to include this limitation. And if the fix takes time, we'll update the portal UI for those resource type to disable static IP for now to avoid confusion.
Kindly let us know if the above helps or you need further assistance on this issue.
Please "Accept the answer" if the information helped you. This will help us and others in the community as well.