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Storage File Data SMB MI AdminAzure built-in role

Allows for admin-level access for managed identities on files/directories in Azure file shares.

Role IDa235d3ee-5935-4cfb-8cc5-a3303ad5995e
CategoryStorage
Actions0
Data actions8

Before you assign it

  • It reaches the data, not just the resource. It has 8 data actions, such as reading blobs, secrets or messages.

What it can do

No control-plane actions.

Data actions

PermissionWhat it allows
Microsoft.Storage/storageAccounts/fileServices/readFileBackupSemantics/actionRead File Backup Semantics Privilege
Microsoft.Storage/storageAccounts/fileServices/writeFileBackupSemantics/actionWrite File Backup Semantics Privilege
Microsoft.Storage/storageAccounts/fileServices/takeOwnership/actionFile Take Ownership Privilege
Microsoft.Storage/storageAccounts/fileServices/runAsBuiltInFileAdministrator/actionPermission that gives built-in admin privilege for file share mounts via managed identity
Microsoft.Storage/storageAccounts/fileServices/fileshares/files/readReturns a file/folder or a list of files/folders
Microsoft.Storage/storageAccounts/fileServices/fileshares/files/writeReturns the result of writing a file or creating a folder
Microsoft.Storage/storageAccounts/fileServices/fileshares/files/deleteReturns the result of deleting a file/folder
Microsoft.Storage/storageAccounts/fileServices/fileshares/files/modifypermissions/actionReturns the result of modifying permission on a file/folder

Assign it

Scope it as tightly as you can: a resource or resource group rather than the whole subscription.

azure cli
az role assignment create \
  --assignee "jane.doe@contoso.com" \
  --role "Storage File Data SMB MI Admin" \
  --scope "/subscriptions/<subscription id>/resourceGroups/<resource group>"
powershell3 lines
New-AzRoleAssignment -SignInName "jane.doe@contoso.com" `
  -RoleDefinitionName "Storage File Data SMB MI Admin" `
  -Scope "/subscriptions/<subscription id>/resourceGroups/<resource group>"
bicep7 lines
resource assignment 'Microsoft.Authorization/roleAssignments@2022-04-01' = {
  name: guid(resourceGroup().id, principalId, 'a235d3ee-5935-4cfb-8cc5-a3303ad5995e')
  properties: {
    roleDefinitionId: subscriptionResourceId('Microsoft.Authorization/roleDefinitions', 'a235d3ee-5935-4cfb-8cc5-a3303ad5995e')
    principalId: principalId
  }
}

Who already has it?

kql · azure resource graph
authorizationresources
| where type == "microsoft.authorization/roleassignments"
| where tostring(properties.roleDefinitionId) endswith "a235d3ee-5935-4cfb-8cc5-a3303ad5995e"
| project principalId = tostring(properties.principalId), principalType = tostring(properties.principalType), scope = tostring(properties.scope)

Other storage roles

Find the smallest role for a task →

Sources