An Azure service that provides private connections between Azure datacenters and infrastructure, either on premises or in a colocation environment.
Azure provides multiple redundant paths and control planes so that loss of the Azure portal (https://portal.azure.com) does not block access to resources or DR operations.
Key points for DR if the Azure portal is unavailable:
- Use alternative control planes instead of the portal
- Azure Resource Manager is the unified control plane for Azure services. If the portal is unavailable, use:
- Azure CLI
- Azure PowerShell
- Azure REST APIs
- These tools allow performing critical DR tasks such as rerouting traffic, scaling resources, or failing over services without relying on the portal.
- This aligns with guidance to avoid a dependency on a single tool like the Azure portal for failover and reconfiguration.
- Azure Resource Manager is the unified control plane for Azure services. If the portal is unavailable, use:
- Plan redundant ingress and routing paths
- For mission-critical web applications, design a redundant ingress path so that traffic can be rerouted if a primary path or control surface is impacted.
- Example patterns include:
- Using Azure Front Door with Azure Traffic Manager as an alternate global router.
- Defining a secondary path with alternate services that can become primary when the main path is unavailable.
- The focus is on ensuring traffic can be redirected and services managed even when one path or tool is unavailable.
- Minimize control-plane complexity
- When using Azure-native services, Azure Resource Manager provides a single, consistent control plane.
- Introducing external routing or control planes (for example, third-party DNS or traffic managers) adds complexity and risk; each additional control plane is another point where configuration might diverge.
- DR procedures should explicitly account for how many independent control planes must be used during a failover.
- Design DR for connectivity and networking
- For network-level DR (including ExpressRoute and other connectivity), design non-overlapping redundancy for each dependency in the end-to-end communication path.
- Consider:
- Redundant connectivity paths between on-premises and Azure.
- Geo-redundant designs for ExpressRoute as described in high-availability and DR guidance.
- Ensure routing is architected to avoid asymmetrical routing issues when multiple paths exist.
- Use Azure regions and availability zones for resilience
- For broader DR, use:
- Availability zones for local redundancy.
- Multiple Azure regions for geo-distant redundancy.
- Azure can act as a failover site for workloads running in another region or on-premises.
- Many Azure services have built-in failover and DR capabilities that should be incorporated into DR plans.
- For broader DR, use:
- Continuous validation and DR testing
- DR plans must be tested regularly to ensure operations can be performed without the portal:
- Validate that traffic can be redirected via alternate paths using CLI/PowerShell/REST.
- Confirm both primary and secondary paths can handle expected production load.
- Verify security posture on all paths, including during degraded states.
- DR plans must be tested regularly to ensure operations can be performed without the portal:
- Azure DNS and core services
- Azure DNS is highly available by design and does not require separate DR uplift.
- Other networking components (virtual networks, firewalls, ExpressRoute) should be included in DR design and, where applicable, replicated or configured for high availability.
In practice, a DR plan for “loss of portal.azure.com” should explicitly document:
- CLI/PowerShell/REST procedures for critical operations (failover, scaling, routing changes).
- Alternate global routing strategy (for example, Azure Traffic Manager in front of or alongside Azure Front Door).
- Network and ExpressRoute redundancy design.
- Regular DR drills that assume the portal is unavailable.
References:
- Global routing redundancy for mission-critical web applications
- Disaster recovery architecture for an Azure data platform
- Disaster recovery design
- Disaster recovery scenario details for an Azure data platform
- Architecture strategies for designing for redundancy
- Architecture strategies for disaster recovery
- Disaster recovery for an Azure data platform