Notes from Azure Backup Deep Dive Whitepaper

The 14 paged Azure Backup Deep Dive Whitepaper[PDF] written by Adin Ermie and Charbel Nemnom covers MARS & IaaS VM Level Backup but not hybrid Azure Backup related technologies, such as System Center Data Protection Manager (SC DPM), and the Microsoft Azure
Backup Server (MABS).

Key points are paraphrased below along with info from other online resources -

* The MARS in Azure Backup (MARS) Agent stands for "Microsoft Azure Recovery Services"...ever since Microsoft combined the Azure Backup (ABU), and the Azure Site Recovery (ASR) services together under the "Azure Recovery Services" label, these two technologies work as 2 pieces in the same puzzle of "recovery" -

* In case of System Center Data Protection Manager (SC DPM), or the Microsoft Azure Backup Server (MABS),  there is a main server that performs the processing, coordination, etc. of the agents, backup/recovery jobs - kind of like the air traffic controller between the source (i.e. the Agent), and the destination (i.e. the storage) locations. Recovery Services Vault (RSV) is like the cloud version of SC DPM, and MABS.

* In the Recovery Services Vault (RSV), we have some collective data about all the data "airplanes" that are flying into the vault's "airport". If the Azure Backup (MARS) Agent is the "airplane", and the Recovery Services Vault (RSV) is the "air traffic controller", then the underlying Azure Storage would be the "tarmac" or "runway".

* The Storage Account Type that is used is General Purpose vl Storage. This is because a General Storage account can be used for Blobs and Azure virtual machine disks.

* Azure Backup does not perform deduplication of the data that is transferred into the Recovery Services Vault (RSV). You may wonder why this is. Although this may cause the amount of storage used to maintain the backups to increase slightly, it allows for a faster recovery of that data. And, since Azure Backup only backs up incremental changes (after the initial full backup), the slight increase to the storage usage is minor.

* In a traditional approach, a third-party backup solution requires some sort of media server that acts like the brains of the operation. This primary server also requires attached storage (in large quantities) to store the backup data. Even when these types of solutions adapt to a cloud model, they treat the cloud as a storage endpoint or destination. Effectively, they view the cloud as just another disk or tape location. The overhead on a solution like this, is having to manage and maintain the Storage Account that this 'media' server operates on; not to mention the patching, management, security, monitoring, etc. Now, of course, storage is virtually endless in a cloud environment, but there are still limitations imposed on the number of IOPS throughput you can achieve, the bandwidth into the storage, etc.

* Another powerful point to using Azure Backup is that the Recovery Services Vault (RSV) is the "brains" of the operation, without the overhead of needing to patch, maintain, manage yet another Virtual Machine in the environment. Remember, third-party solutions require some sort of 'media' server that coordinates everything. And you need to maintain this system, including security, OS hardening, networking and communications not only to/from the Agents, but to the storage subsystem, etc.

* With Azure Backup we have the following features:
Full Virtual Machine level backups
No management infrastructure to patch, maintain, etc.
Endless storage, without needing to maintain and manage the Storage Account
File/Folder level restore out of the VM-level backup, without having to restore the entire VHD file first to browse and find your target file
Backup VMs with disk sizes up to 4TB(4095GB), both managed and unmanaged.

* Azure Backup uses Block Blob storage for backing up your instances. You have the flexibility to choose between locally redundant storage (LRS) or geo-redundant storage (GRS). Both LRS and GRS are Block Blob Storage. Cost of locally redundant storage is roughly two times that of geo-redundant storage

* The Protected Instances calculation is based on the actual size of the virtual machine, which is the sum of all the data in the virtual machine--excluding the temporary storage.

* Microsoft guarantees at least 99.9% availability of the backup and restore functionality of the Azure Backup service. Availability is calculated over a monthly billing cycle.

* Backups run when a machine is shut down. The recovery point is marked as crash consistent.

* Application-consistent backups feature in Azure Backup became Generally Available in February, 2018. This feature helps ensure that your application backup data (for various applications like Oracle, MySQL, Mongo DB, SAP HANA, and PostGreSQL) is transactionally consistent.  This Azure native solution offers ease of management and uniform backup experience for all Azure resources.

* Azure Marketplace offers pre-loaded Oracle with EE or SE (BYOL) – MS Windows only. To backup Oracle Database, Application-consistent backup feature in Azure Backup or Azure File storage can be used

* 3-minute video tutorial on taking application consistent backup of MySQL 5.7.17 database running on Ubuntu in Azure VM using Azure Backup

Comments