It has been days since Microsoft announced the Public Preview of Azure Backup via Azure Recovery Services. In this post I will enumerate the different features and limitations of the service, to help you decide if it fits your needs.
NB : This post is only related to IaaS part of Azure Backup
The following is the agenda of this post :
Introduction to Azure Backup via Recovery Services
Azure Backup for Azure IaaS features (Current and Coming)
Azure Backup for Azure IaaS limitations
1- Introduction to Azure Backup via Recovery Services
Azure Backup was released first time under Azure Backup vaults, and it was only supporting classic Azure IaaS (Azure Service Management ie IaaS v1). With the GA of the Azure Resource Manager stack on summer 2015, IaaS V2 users were not able to use Azure Backup to protect their V2 virtual machines. This was the first blocker of the ARM stack adoption and one of the most wanted feature regarding the ARM platform.
After 10 months of struggle, Microsoft announced the Public Preview of Azure Backup supporting IaaS V2 virtual machines. It’s a real alleviation for Azure IaaS V2 users, but also for all Azure users planning to use Azure backup features. The main difference is that Azure Backup is now part of Azure Recovery Services vaults, and no longer Azure Backup vaults. Azure Backup vaults still exist under the ASM stack, but it’s clear that sooner or later, all will be integrated to Azure Recovery Services.
Azure Recovery Services include both Azure Backup and Azure Site Recovery supporting both ASM and ARM stacks. This is what we call great news:
- Azure Recovery Services is integrated to the new portal (Ibiza portal)
- Azure Backup and ASR under Recovery Services vaults support both ASM and ARM stacks
Azure Backup under Recovery Services vaults support the 4 backup scenarios:
- Azure Backup Server or Agent based:
- Azure Backup Agent to Azure –> Backup files and foders to Azure Storage
- Azure Backup with System Center Data Protection Manager –> Backup Hyper-V VMs, SQL server, SharePoint, files and folders to Azure Storage
- Azure Backup with Azure Backup Server (MABS, code name Venus) –> Backup Hyper-V VMs, SQL server, SharePoint, files and folders to Azure Storage
- Azure Backup on the Azure Service Fabric :
- Azure Backup for IaaS VMs –> Backup Classic and ARM Azure Virtual Machines
This post will only detail Azure Backup for IaaS virtual machines
2- Azure Backup for Azure IaaS features (Current and Coming)
Azure Recovery Services is currently under Public Preview. The following are the features of Azure Backup and the expected features that will come with GA:
- Backup and Restore ARM and ASM Azure virtual machines (V1 and V2)
- Based on backup policies : Two backup schedules exist : Daily and Weekly. This way you can define backups which occur daily or weekly
- Azure Backup provides different retention periods possibility : Daily, Weekly, Monthly and yearly. Microsoft officially stated a maximum retention period of 99 years, however, thanks to Azure Backup flexibility, you can have unlimited retention period, up to 9999 years. This way, you can achieve long term retention using the same policy and mechanism (9999 days for daily backups, 9999 weeks for weekly backups,9999 months for monthly retentions ,9999 years for yearly retention)
- Azure Backup provides 3 recovery point consistency types : Application, File and Crash consistent recovery points. You can consult the documentation to get the requirements and prerequisites for each type
- The Backup Vault’s Storage redundancy can be GRS or LRS. GRS is more secure (Data is replicated between two regions) but more expensive (LRS *2), LRS is less secure (Locally Redundant) but cheaper. As per my experience, because the Azure Backup pricing is per protected instance (And the price is relatively high), you will notice that the Storage cost is a small fraction of the Azure Backup instances cost, so using GRS will not really impact the bill.
- Azure Backup use incremental backups : The first recovery point is a full backup, the next ones are incremental backups : This reduce the consumed backup storage. Due to the Azure Backup design and mechanism, incremental backups will not impact the restore time.
- Simple pricing model : The cost of Azure Backup is like the following : Total Cost = Instance Cost + Consumed Storage. If you know the daily change or growth of your data, than you can easily predict the backup cost. See this link for Azure Backup pricing : https://azure.microsoft.com/en-us/pricing/details/backup/
- A backup operation consist of two phases : Snapshot phase and Data transfer phase. The snapshot phase occur when the scheduled moment comes. The data transfer he backup vault begins just after the snapshot completion. This operation lay take up to 8 hours during rush hours but will always completes before 24 hours.
- Azure Backup provides 99,99 availability SLA for Backup and Restore, monthly based. This is only applicable for the GA product.
- Currently, two restore options are available
- To a Virtual Machine : A new Virtual Machine is created
- To a Storage Account : VHDs can be restored to a Storage Account
- I expect some features to come with and post GA, but this my own thoughts, since this is what actually implemented with DPM and MABS :
- Backup/Restore of Files and folders from a VM recovery point
- Backup/Restore SQL or/and MySQL databases directly from a VM
3- Azure Backup for Azure IaaS limitations
- Azure Backup does not currently support Premium Storage virtual machines. This feature will released probably during the GA
- Currently, the daily backup supports 1 recovery point per day ie you cannot backup a Virtual Machine more than once time a day. To achieve this, use the ‘manual backup’ to schedule more than one backup a day. Keep in mind that two simultaneous backups are not supported, so you will need to wait for the first once to compete before triggering the next one.
- The Azure VM agent and the Backup extension are required to achieve Application or File consistent recovery points. Otherwise, the recovery point will be crash consistent. Be careful of the Azure VM and Backup agents network requirements
- The ‘Backup now’ operation does not replace a ‘Snapshot’ mechanism if you want to rapidly restore a VM (The recovery point may take up to 8 hours to be available)
- Currently, the Restore to a VM is not very customizable : You cannot choose a number of properties like Storage Container, VHDs names, NIC names … To have control of the created VM, you can restore the VHDs to a storage account and use a script or template to create a VM with the configuration of your choice.
- There is no notification system built-in with Azure backup. So you can’t at this stage configure notifications for the backup jobs statuses. However, there possible alternate methods to do it : When Powershell will be supported, you can create automation scripts which get the Backup jobs statuses and make the notifications. You can also use the Azure Audit logs since the Backup operations are logged within them
- No Powershell support, but will be released with GA
- You cannot edit en exiting policy. If you want to change a policy, you will need to create a new one and change the VM’s assignment. Things will change by GA, so no worry
- You cannot change the vault Redundancy type once you configured at least one backup. You need to change the redundancy before any data is being transferred to the vault
- There some limitations about the backup / restore possibilities, I will rephrase here the documentation
- Backing up virtual machines with more than 16 data disks is not supported.Backing up virtual machines with a reserved IP address and no defined endpoint is not supported.
- Backing up virtual machines by using the Azure Backup service is supported only for select operating system versions:
- Linux: See the list of distributions that are endorsed by Azure. Other Bring-Your-Own-Linux distributions also should work as long as the VM agent is available on the virtual machine.
- Windows Server: Versions older than Windows Server 2008 R2 are not supported.
- Restoring a domain controller (DC) VM that is part of a multi-DC configuration is not supported.
- For classic VMs, restore is supported to only new cloud services.
- Restoring virtual machines that have the following special network configurations is supported through restoring disks to a desired storage account and using PowerShell to attach restored disks to VM configuration of choice. To learn more, see Restoring VMs with special network configurations.
- Virtual machines under load balancer configuration (internal and external)
- Virtual machines with multiple reserved IP addresses
- Virtual machines with multiple network adapters