RavenDB PeriodicExport Error "RequestEntityTooLarge"

We created PeriodicExport for RavenDB database. We try to upload backup files to Azure BLOB Container.

There are our settings:

In the Azure BLOB Container I can see incremental backup files. But I do not see full backups files.

Also I can see next error form the Raven Alerts:

And there is full exception information:

Raven.Abstractions.Connection.ErrorResponseException: Status code: RequestEntityTooLarge
<?xml version="1.0" encoding="utf-8"?><Error><Code>RequestBodyTooLarge</Code><Message>The request body is too large and exceeds the maximum permissible limit.
RequestId:8b013757-401e-0014-4965-b7e992000000
Time:2021-10-02T08:13:54.8562742Z</Message><MaxLimit>67108864</MaxLimit></Error>

   at Raven.Database.Client.Azure.RavenAzureClient.PutBlob(String containerName, String key, Stream stream, Dictionary`2 metadata) in c:\Builds\RavenDB-Stable-3.0\Raven.Database\Client\Azure\RavenAzureClient.cs:line 93
   at Raven.Database.Bundles.PeriodicExports.PeriodicExportTask.UploadToAzure(String backupPath, PeriodicExportSetup localExportConfigs, Boolean isFullBackup) in c:\Builds\RavenDB-Stable-3.0\Raven.Database\Bundles\PeriodicExports\PeriodicBackupTask.cs:line 397
   at Raven.Database.Bundles.PeriodicExports.PeriodicExportTask.<>c__DisplayClasse.<<TimerCallback>b__a>d__10.MoveNext() in c:\Builds\RavenDB-Stable-3.0\Raven.Database\Bundles\PeriodicExports\PeriodicBackupTask.cs:line 248

Raven DB version is:

{
  "ProductVersion": "3.0.0 / cdc39ac / ",
  "BuildVersion": "3690"
}

It is possible to fix this error?

Any help is much appreciated.

UPDATE

I have found source code of the relevant build version in GitHub repository.

The bug exists in the next method:

public void PutBlob(string containerName, string key, Stream stream, Dictionary<string, string> metadata)
{
    var url = GetUrl(containerName) + "/" + key;

    var now = SystemTime.UtcNow;
    var content = new StreamContent(stream)
                  {
                      Headers =
                      {
                          { "x-ms-date", now.ToString("R") }, 
                          { "x-ms-version", "2011-08-18" },
                          { "x-ms-blob-type", "BlockBlob" },
                          { "Content-Length", stream.Length.ToString(CultureInfo.InvariantCulture) }
                      }
                  };

    foreach (var metadataKey in metadata.Keys)
        content.Headers.Add("x-ms-meta-" + metadataKey.ToLower(), metadata[metadataKey]);

    var client = GetClient(TimeSpan.FromHours(1));
    client.DefaultRequestHeaders.Authorization = CalculateAuthorizationHeaderValue("PUT", url, content.Headers);

    var response = client.PutAsync(url, content).ResultUnwrap();

    if (response.IsSuccessStatusCode)
        return;

    throw ErrorResponseException.FromResponseMessage(response);
}

As you can see this method use Azure API version 2011-08-18. Limitations for this Azure version described in the Microsoft documentation.

Regarding documentation "Maximum blob size via single write operation (via Put Blob)" is exactly 64 MiB (67108864 bytes). So exception provided by Azure is absolutely correct.

Unfortunately Raven Build-3690 has a bug, that was fixed in the next version. Source code with fixes can be reviewed here.