Today we will cover the several reasons for a collection limit – azure backup can fail
Here we can detect the error as shown:
OperationNotAllowed : The number of restore points across restore point collections and resource groups for a VM cannot exceed 18. To create a new restore point, please delete existing restore points.
Please ensure that there are no resouce locks which prevents Restore points cleanup. Refer the troubleshooting guide at http://aka.ms/usererrorrpcollectionlimitreached.
To resolve the situation you will have to ensure no Resource locks have been inherited in the Backup Vault
Option 1 ( Remove Snapshot ) – Safe Option
Clean up restore point collection from Azure portal
To manually clear the restore points collection, which isn’t cleared because of the lock on the resource group, try the following steps:
1.Sign in to the Azure portal.
2.On the Hub menu, select All resources, select the Resource group with the following format AzureBackupRG_<Geo>_<number> where your VM is located.
3.Select Resource group, the Overview pane is displayed.
4.Select Show hidden types option to display all the hidden resources. Select the restore point collections with the following format AzureBackupRG__.
3.Select Delete to clean the restore point collection.
4.Retry the backup operation again.
Option 2 ( Remove previous backups)
In the vault select the item to stop backup:
Enable the backup once cleaned up