Microsoft Azure Backup Service, abbreviated to MABS, is a simple to use, widely applicable backup service for a wide range of scenarios. MABS "knows" about different Azure workloads providing native integration with virtual machines and VMs running SAP HANA, SQL Server, and Azure Files.

Azure Backup Service saves backup data to blob storage, which can be specified as locally redundant (LRS), geo-redundant (GRS), or readable geo-redundant (RA-GRS). As your workloads' data grows, MABS ensures enough storage to accommodate the increased backup volume. 

In the case of virtual machines and Azure files, Azure Backup Service can take snapshots, dramatically reducing restore time.

You set policies to specify when backups should be taken and how long backups should be retained before permanent deletion. You can also have backup data transition through states of retention. Initially, it will be backed up to more accessible operational storage, then after a user-specified period archived to vault storage. Azure Backup Service will manage this process automatically. MABS has soft delete functionality, retaining deleted backups for 14 days, allowing recovery of accidentally deleted data.

Backed-up data is encrypted in transit and at rest with either Microsoft-managed keys or your own customer-managed keys. MABS can backup and restore Azure virtual machines that use Azure Disk Encryption on OS and data disks.

Azure Backup uses Recovery Services and Backup vaults to manage backups, and it is through vaults' role-based access control you manage user access to backed-up data. Vaults, in turn, are aligned to subscriptions, so it's best to settle on a subscription hierarchy design early on in the cloud adoption process.

Not only does Azure Backup Service integrate with workloads, but also with Log Analytics to provide monitoring and reporting. As well as the Azure portal, MABS functionality can be accessed via the Backup Center, Vault dashboards, Azure Resource Manager templates, PowerShell, CLI, and REST APIs.

Azure Backup Service default settings are geo-redundant for storage replication. This setting can not be changed once the backup is fully configured. By default, soft delete is enabled to give you 14 days grace to recover unintended backup deletion, accidental or otherwise. Cross-Region Restore to an Azure paired region is available for virtual machines, SQL Server on VMs, and SAP HANA on VMs workloads.

Retention is classified as short term when measured in minutes or days and long term for weekly, monthly, and yearly. If you choose to stop backing up a resource, you have a couple of options. You can stop protection and retain backup data, which does as it sounds. No more backups are taken, but you do have the option to restore the resource if needed or at least have access to the backup data. This option will allow you to resume backup protection at a future date if required. Alternately, you can stop protection and delete backup data, stopping future backups and deleting all recovery points.

In the context of Azure only backups, as opposed to an on-premises hybrid scenario, Azure Backup Service accesses virtual machines through the Azure network and doesn't need access to your virtual network. Meaning you don't need to set up firewall rules or make any explicit network allowance to enable backups to take place. 

MABS is an all-encompassing backup service baked into Azure's core infrastructure. Let's see how we can apply its functionality to SAP workloads.