Support to disable Diagnostics settings (classic) of Storage Account in Bicep

[vienleidl]

Issue
Diagnostics are enabled by default on new storage accounts created from the Azure portal, PowerShell and Azure Bicep. In the diagnostic settings (classic) blade, hour metrics are always enabled by default for blob, file, table & queue services, on the new-created Storage Account.

Expected solution
It would be better if we can turn diagnostics on or off by using Azure Bicep.

[jikuja]

Looks like this settings in on data layer => not modifiable with ARM/Bicep directly.

E.g. Disable blob metrics is PUT request on https://xxxxxxx.blob.core.windows.net/?restype=service&comp=properties&_=1728627741675&sv=2022-11-02&ss=bqtf&srt=sco&sp=rwdlacuptfxiy&se=2024-10-11T14:18:58Z&sig=XXXXXXX

with payload of

<?xml version="1.0"?>
<StorageServiceProperties>
  <Logging>
    <Version>1.0</Version>
    <Read>false</Read>
    <Write>false</Write>
    <Delete>false</Delete>
    <RetentionPolicy>
      <Enabled>false</Enabled>
    </RetentionPolicy>
  </Logging>
  <HourMetrics>
    <Version>1.0</Version>
    <Enabled>false</Enabled>
    <RetentionPolicy>
      <Enabled>false</Enabled>
    </RetentionPolicy>
  </HourMetrics>
  <MinuteMetrics>
    <Version>1.0</Version>
    <Enabled>false</Enabled>
    <RetentionPolicy>
      <Enabled>false</Enabled>
    </RetentionPolicy>
  </MinuteMetrics>
</StorageServiceProperties>

---

Even classic metric persist in on by default, it does save metrics because Azure Storage will retire classic metrics on January 9, 2024. To transition to Azure Monitor metrics, see[Azure Storage metrics migration](https://learn.microsoft.com/azure/storage/common/storage-metrics-migration?WT.mc_id=Portal-Microsoft_Azure_Storage)

Default state on portal:

Default state XML:

<?xml version="1.0" encoding="utf-8"?>
<StorageServiceProperties>
  <Logging>
    <Version>1.0</Version>
    <Read>false</Read>
    <Write>false</Write>
    <Delete>false</Delete>
    <RetentionPolicy>
      <Enabled>false</Enabled>
    </RetentionPolicy>
  </Logging>
  <HourMetrics>
    <Version>1.0</Version>
    <Enabled>true</Enabled>
    <IncludeAPIs>true</IncludeAPIs>
    <RetentionPolicy>
      <Enabled>true</Enabled>
      <Days>7</Days>
    </RetentionPolicy>
  </HourMetrics>
  <MinuteMetrics>
    <Version>1.0</Version>
    <Enabled>false</Enabled>
    <RetentionPolicy>
      <Enabled>false</Enabled>
    </RetentionPolicy>
  </MinuteMetrics>
  <Cors/>
  <DeleteRetentionPolicy>
    <Enabled>true</Enabled>
    <Days>30</Days>
    <AllowPermanentDelete>false</AllowPermanentDelete>
  </DeleteRetentionPolicy>
  <StaticWebsite>
    <Enabled>false</Enabled>
  </StaticWebsite>
</StorageServiceProperties>

---

Bicep/ARM folks are probably going to ask if you have opened support request because this is fixable on by the product group / on resource provider.

[vienleidl]

Long time ago, after the Storage Account had been newly created, the Storage logging data ($log blob container) were recorded accordingly. Now only Hour metrics are enabled by default for those 4 storage services.

I have to run the following PowerShell script to turn off those Storage Analytics metrics after the Storage Accounts have been created with Bicep templates,

Write-Host "Starting the process to turn off Diagnostic settings (classic) of related Storage Accounts..." -ForegroundColor Green
$StorageAccounts = (Get-AzStorageAccount -ResourceGroupName $ResourceGroupName)

ForEach ($StorageAccount in $StorageAccounts) {  
    $StorageContext = $StorageAccount.Context
    Write-Host "Turning off the Diagnostic settings (classic) of the Storage Account: $($StorageAccount.StorageAccountName)" -ForegroundColor Blue
    Set-AzStorageServiceMetricsProperty -MetricsType Hour -MetricsLevel None -Context $StorageContext -ServiceType Blob
    Set-AzStorageServiceMetricsProperty -MetricsType Hour -MetricsLevel None -Context $StorageContext -ServiceType File
    Set-AzStorageServiceMetricsProperty -MetricsType Hour -MetricsLevel None -Context $StorageContext -ServiceType Table
    Set-AzStorageServiceMetricsProperty -MetricsType Hour -MetricsLevel None -Context $StorageContext -ServiceType Queue
}

TBH, I don't understand what the retirement of classic metrics (Storage Analytics metrics) means 😉, because as of now I can see it is still enabled by default.