Azure Disk Snapshots vs Azure Virtual Machine Backup vs Azure Site Recovery

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October 23, 2022

Table Of Content

Here’s a detailed comparison of Snapshots, Azure Backup, and Azure Site Recovery (ASR) to help understand their differences and use cases:

1. Purpose

Feature	Snapshots	Azure Backup	Azure Site Recovery (ASR)
Primary Use Case	Point-in-time disk snapshots for quick recovery or migration.	Long-term data retention and recovery for compliance and disaster recovery.	Disaster recovery with real-time replication to a secondary region or site.
Scope	Individual VM or disk.	Full VMs, files, and specific workloads like databases.	Entire VM workloads for region/site-level failover.

2. Backup and Recovery Features

Feature	Snapshots	Azure Backup	Azure Site Recovery (ASR)
Granularity	Per disk (OS or data disks).	Whole VM, disks, files, folders, or databases.	Entire VM or application workloads.
Recovery Options	Restore individual disks or VMs from snapshots.	Restore full VMs, disks, or individual files.	Failover VMs to a secondary region or site.
Data Consistency	Crash-consistent snapshots.	Crash-, file-system-, or application-consistent backups.	Application-consistent replication and recovery.

3. Retention and Cost

Feature	Snapshots	Azure Backup	Azure Site Recovery (ASR)
Retention Period	Short-term, typically for temporary needs.	Short-term and long-term retention policies (daily, weekly, monthly, yearly).	No retention; focuses on continuous replication.
Cost	Charged for snapshot storage on Managed Disks (standard or premium).	Recovery Services Vault costs (backup storage and operations).	Pay for ASR replication, storage, and failover.

4. Automation and Management

Feature	Snapshots	Azure Backup	Azure Site Recovery (ASR)
Automation Support	Supports custom automation with scripts or Azure CLI/PowerShell.	Fully automated via Azure Backup policies.	Supports automated failover and failback orchestration.
Management	Manual creation and management of snapshots.	Centrally managed in Recovery Services Vault.	Managed via the Azure portal or PowerShell for replication and failovers.

5. Disaster Recovery

Feature	Snapshots	Azure Backup	Azure Site Recovery (ASR)
Region-Level Disaster Recovery	Not suitable; snapshots are stored in the same region as the disk.	Geo-redundant storage (GRS) can provide recovery in another region.	Designed specifically for region/site disaster recovery.
Failover Support	None.	Manual restore process to rebuild VMs.	Automated failover to secondary regions or sites.

6. Security Features

Feature	Snapshots	Azure Backup	Azure Site Recovery (ASR)
Encryption	Encrypted at rest using Azure Disk Encryption.	Encrypted at rest with options for customer-managed keys (CMK).	Encrypted replication data in transit and at rest.
Soft Delete	Not available.	Protects against accidental or malicious deletion.	Not applicable; replication is continuous.

When to Use Each Option

Scenario	Snapshots	Azure Backup	Azure Site Recovery (ASR)
Quick Recovery of Disks/VMs	YES. Ideal for short-term, point-in-time recovery.	Useful but may take longer than snapshots.	Not designed for short-term recovery.
Long-Term Retention	NO. Not suitable for long-term retention.	YES. Best choice with customizable policies.	NO. No retention capabilities.
Disaster Recovery (Region-Level)	NO. Not suitable; snapshots are region-specific.	YES. Possible with geo-redundant storage (GRS).	YES. Best choice for automated region failover.
Compliance and Regulatory Needs	NO. Not compliant for most regulations.	YES. Designed for compliance scenarios.	NO. Not focused on compliance.
Application-Level Replication	NO. Does not support app-level replication.	YES. Application-consistent backups available.	YES. Provides app-consistent replication.
Cost-Efficient Point-in-Time Protection	YES. Cost-effective for temporary snapshots.	More expensive due to backup vault costs.	Costlier because of continuous replication.

Summary of Recommendations

Use Snapshots:
- For short-term protection or quick recovery of disks/VMs.
- Ideal for testing, migrations, or development scenarios.
Use Azure Backup:
- For long-term retention, compliance, and file-level recovery.
- Best for protecting VMs against accidental deletion or corruption.
Use Azure Site Recovery (ASR):
- For disaster recovery with automated failover and failback capabilities.
- Essential for high availability and business continuity during region or site outages.

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Learn how to implement Azure Site Recovery

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About the Author

Rajnish Kumar Jha

MCT, MCSA, MCSE, MCAD, MCPD, MCTS, MCSD

My name is Rajnish Kumar Jha. I am Technical architect on Azure Cloud and .NET since 21+ years. I’ve worked for pioneer companies and as freelance trainer/consultant helping my clients to achieve their IT goals.

I find blogging, a great way to share back what I’ve learned all through my professional journey. You are welcome to connect or share feedback/suggestion here or through an email.