Disaster Recovery practice questions

Azure Backup

Why wrong: Azure Backup provides point-in-time backups, not continuous replication, and does not support non-disruptive failover testing.

Azure Traffic Manager

Why wrong: Traffic Manager performs DNS-based traffic routing across regions, not VM replication or failover.

Azure Blueprints

Why wrong: Azure Blueprints is a governance tool for defining repeatable environments, not a disaster recovery solution.

Azure SQL Managed Instance

Why wrong: Managed Instance provides near 100% SQL Server compatibility but does not support elastic pools. It is better suited for migrations requiring instance-scoped features.

Azure Database for MySQL

Why wrong: Azure Database for MySQL is a fully managed MySQL database, but it does not provide elastic pools for sharing resources across databases.

Azure Database for PostgreSQL

Why wrong: Azure Database for PostgreSQL is a fully managed PostgreSQL service, but it lacks elastic pool functionality.

Use a Recovery Services vault with Locally Redundant Storage (LRS) and enable cross-region restore

Why wrong: Cross-region restore requires geo-redundant storage (GRS); LRS stores data only in the primary region, so it cannot be restored to a secondary region.

Use Azure Site Recovery to replicate the entire VM to the secondary region

Why wrong: Site Recovery is for disaster recovery with continuous replication, not for backup with long-term retention. It does not provide the backup compliance features required.

Manually copy backup snapshots to a storage account in the secondary region

Why wrong: Manual copying is not automated, prone to errors, and does not integrate with Azure Backup's management and retention policies.

Azure Backup (MARS agent)

Why wrong: Azure Backup is designed for backup, not DR. It can take application-consistent backups but does not support rapid failover with an RTO of less than 4 hours. Failover would require restoring from backup, which takes longer.

Azure Migrate

Why wrong: Azure Migrate is for discovering, assessing, and migrating on-premises workloads to Azure. It does not provide ongoing replication or failover capabilities for DR.

Azure File Sync

Why wrong: Azure File Sync syncs on-premises file servers to Azure file shares. It does not replicate entire physical servers or support failover of applications.

SQL Server log shipping to a VM in the secondary region

Why wrong: Log shipping requires SQL Server configuration and manual failover, and it does not provide automated testing capabilities. The RTO of 1 hour may be difficult to guarantee.

Azure Backup with cross-region restore

Why wrong: Azure Backup provides point-in-time restore but typically has higher RTO (hours to days) and does not support automated failover or non-disruptive drills.

Azure SQL Database geo-replication

Why wrong: Geo-replication is for Azure SQL Database only, not for SQL Server on Azure VMs. The database is on a VM, so this service does not apply.

Azure Site Recovery for VMs and active geo-replication for the database

Why wrong: Active geo-replication is only available for Azure SQL Database (single), not for Azure SQL Managed Instance.

Azure Backup for VMs and auto-failover groups for the database

Why wrong: Azure Backup is designed for data backup and restore, not for replication with an RTO of 2 hours, and does not provide automatic VM orchestration.

Deploy a second region with VMs and database replicas manually configured and Azure Traffic Manager

Why wrong: Manual deployment does not provide automated replication and failover, and does not meet the RPO/RTO requirements as efficiently as native Azure services.

Enable application-consistent recovery for all VMs and use ExpressRoute.

Why wrong: Application-consistent recovery incurs additional overhead and cost; ExpressRoute improves network reliability but does not minimize replication costs.

Use standard recovery plans and default replication policy.

Why wrong: Default replication creates recovery points every 5 minutes, which may be more frequent than needed and incurs higher costs without meeting the consistency requirement across VMs.

Configure a single recovery plan with manual failover and use Premium SSD managed disks.

Why wrong: Manual failover does not ensure consistent recovery points across VMs, and Premium SSD increases cost without addressing the RPO or consistency.

Azure SQL Database backup to geo-redundant storage

Why wrong: Geo-restore from backups has a higher RPO (1 hour) and RTO (12 hours), not meeting requirements.

Azure SQL Database with zone-redundant configuration

Why wrong: Zone redundancy protects against datacenter failure within a region, not a regional disaster.

Azure SQL Database with failover group using manual failover

Why wrong: Manual failover requires human intervention and may not meet the RTO of 1 hour for automatic failover.

SQL Server Failover Cluster Instance (FCI)

Why wrong: FCI provides high availability at the instance level using shared storage, but it does not support synchronous replication or read-only secondary replicas for reporting.

Azure Site Recovery

Why wrong: Azure Site Recovery is a disaster recovery solution that replicates VMs across regions. It is not designed for high availability within a single region and does not guarantee zero data loss.

Azure Backup

Why wrong: Azure Backup provides backup and restore capabilities but does not offer automatic failover or replication for high availability.

Azure Backup

Why wrong: Azure Backup provides backup and restore capabilities but does not include orchestrated failover or replication for disaster recovery.

Azure Migrate

Why wrong: Azure Migrate is used for assessment and migration of on-premises workloads to Azure, not for ongoing disaster recovery replication.

Azure Disaster Recovery

Why wrong: There is no Azure service named 'Azure Disaster Recovery'; the correct service is Azure Site Recovery.

Network mapping and IP customization

Why wrong: These are important for network configuration during failover but do not control startup order or provide drill capabilities.

Replication policy with crash-consistent snapshots

Why wrong: Crash-consistent snapshots are a replication option but do not address startup sequencing or testing.

Azure Automation runbooks and Azure Monitor alerts

Why wrong: Automation runbooks can be used in Recovery Plans, but this combination is incomplete; alerts are not needed for the core requirement.

Azure Site Recovery

Why wrong: Incorrect. Azure Site Recovery typically has an RPO of several minutes, which does not meet the sub-15-second requirement.

Azure Backup for SQL Server

Why wrong: Incorrect. Azure Backup provides point-in-time restore but has a typical RPO of hours and RTO that is not suitable for sub-1-hour recovery.

Geo-redundant backups

Why wrong: Incorrect. Geo-redundant backups are for storage-level redundancy and do not provide the required low RPO/RTO for a SQL Server database.

Azure Cosmos DB for NoSQL

Why wrong: Cosmos DB is NoSQL and does not support complex SQL queries natively.

Azure SQL Database Hyperscale

Why wrong: Hyperscale is for large databases and high throughput, not specifically optimized for read-heavy low-latency.

Azure SQL Managed Instance Business Critical

Why wrong: Managed Instance has limited geo-replication support and higher latency than SQL Database.

Enable active geo-replication for the database.

Why wrong: Active geo-replication alone requires manual failover; does not provide automatic failover.

Set up log shipping to a secondary server.

Why wrong: Log shipping is not a built-in feature for Azure SQL Database; it's for on-premises.

Deploy Azure Site Recovery to replicate the SQL Server VM.

Why wrong: Azure SQL Database is PaaS, not a VM; Site Recovery is not applicable.

Azure Database for PostgreSQL

Why wrong: Not a SQL Server migration target.

SQL Server on Azure Virtual Machines with Always On availability groups

Why wrong: Requires manual setup and management.

Azure SQL Managed Instance with failover groups

Why wrong: Failover groups provide automated failover but are not as seamless as active geo-replication.

Long-term retention (LTR) backups

Why wrong: LTR is for backup retention, not high availability.

Automatic tuning

Why wrong: Automatic tuning is for performance optimization, not high availability.

Transparent Data Encryption (TDE)

Why wrong: TDE is for encryption at rest, not high availability.

Both servers must be in the same Azure region.

Why wrong: They must be in different regions for geo-redundancy.

The databases must be in different elastic pools.

Why wrong: They can be in the same or different elastic pools.

Use Azure SQL Managed Instance for all databases with auto-failover groups.

Why wrong: More expensive and not needed for reporting/archival.

Use Azure Cosmos DB for the customer database, Azure SQL Database for reporting, and Azure Blob Storage for archival.

Why wrong: Cosmos DB is not suitable for relational customer data.

Use Azure SQL Database with active geo-replication for all databases.

Why wrong: Too costly for reporting and archival databases.

Azure Site Recovery with SQL Server replication

Why wrong: Site Recovery provides VM-level replication, not database-level with 15-minute RPO.

Azure Database Migration Service (DMS)

Why wrong: DMS is for migration, not ongoing replication.

Azure SQL Database Managed Instance with transaction replication

Why wrong: Transaction replication is complex and may not meet RPO.