Backup a lot of object

Veeam for M365 can backup Mailbox, OneDrive, Sharepoint and Teams on your Tenant. All these solutions can contain a large amount of data, which will lengthen backup times. In some cases, Error 429 too many requests may appear.

This error is due to the fact that the backup job takes a long time to connect to the Microsoft 365 tenant. This error can be seen in the backup job log. As a reminder, the backup job can be found here :

• %ProgramData%\Veeam\Backup365\Logs\\

On each folder you can found the job logs.

In this case of if backup take very long time, you can modify the Microsoft throttling.

Modify the Microsoft throttling

Throttling consists in reducing the number of requests a tenant can execute. This is done to avoid excessive bandwidth usage to the detriment of other tenants. When the threshold authorized by Microsoft is exceeded, the latter limits the number of requests for a certain period. If there are too many requests, the HTTP 429 error is returned by Microsoft Graph. Subsequent requests then fail. It is therefore necessary to ask Microsoft to modify throttling.

From the Microsoft 365 Admin Center, click on ? then type EWS Throttling Policies Increase.

Click on Run Tests to begin the test and verify if there is a Throttling.

The test is in progress. If Exchange Web Services are Throttled, enter the duration that you want (duration is in days). Check the option I acknowledge clicking “Update settings” will make the changes described above to the tenant configuration. then click on Update.

The policy is been configured.