Introducing Disaster Recovery for containers

Abstract

Learn about the different disaster recovery services for containers.

Disaster recovery allows an organization to maintain or quickly resume mission-critical functions following a disaster that requires manual intervention. The Sitecore Disaster Recovery (DR) service offers two DR service types: DR Basic (confirmation) and DR Managed (automatically). With these go two Infrastructure types: Cold Standby (minimum infrastructure) and Hot Standby (full replica):

  • DR Basic Cold Standby: reactive service. Recovery and failover process will start after the event and requires confirmation of the customer. This is a cost-effective service option with a longer Recovery Time Objective (RTO). The Basic Cold Standby DR service type provisions the minimum infrastructure required and is often used for non-critical applications or in case data only changes infrequently.

    Basic Cold Standby Disaster Recovery includes Geo-Replication. In the event of a disaster, fail over to the secondary region happens and the database with minimal downtime.

  • DR Managed Hot Standby: proactive service. Failback and failover process will start automatically. Provisions an entire replica of the primary site. This provides the shortest RTO interval.

Which recovery option works best for your requirements depends on whether you require a proactive or reactive initiation of failover and how quickly you want to be back online in case of and outage.

The Managed Cloud Containers environment uses Infrastructure as Code (IaC). This means that the provisioning artifacts are stored in Git repositories following GitOps practices. Disaster Recovery also follows these practices. For more information on the containers infrastructure, refer to The Managed Cloud architecture and Deploying in Managed Cloud.

Use the following table as a reference to decide which recovery option works best for your requirements, consider:

  • How quickly your site would need to be back online in the event of an outage.

  • The recovery point objective (RPO).

  • The recovery time objective (RTO).

Specifications

DR Basic Cold Standby

DR Managed Hot Standby

Backup technologies

Geo-Replication (ACR, SQL Server, KeyVault, Blob Storage)

Azure APIs.

Geo-Replication (ACR, SQL Server, KeyVault, Blob Storage)

Azure APIs.

Recovery process

  1. Customer request/approval for failover

  2. Deploy

  3. Switch over

  4. Go live

  5. Customer validation

  1. Switch over

  2. Go live

  3. Customer validation

Secondary environment state

Created on demand

Fully deployed exact replica of the primary environment and up and running

Recovery Point Objective (RPO)

SQL 5 seconds

Applications rely on images in the ACR, thus the RPO is based on the latest images available in the ACR

SQL 5 seconds

Applications rely on images in the ACR, thus the RPO is based on the latest images available in the ACR

Recovery Time Objective (RTO) - Technology only

Failover execution approximately 10 minutes

Includes SQL switchover and AFD Traffic switching

TBC

Failback Time - Technology only

Failover execution approximately 10 minutes

Includes SQL switchover and AFD Traffic switching

TBC

Note

The technology RTO values depend on how long the system takes to restore the Sitecore platform. If manual steps are required involving the customer or partner, this may extend the effective RTO.

A typical Sitecore environment consists of the following Azure resource types:

  • KeyVault - Azure provides a read-only replication to the secondary environment and this allows the continued operation of Sitecore in the secondary environment.

  • Storage Account - Object replication provided in the Storage account is used to selectively replicate containers to the secondary environment.

  • ACR – ACR and its images are provisioned using terraform. The infrastructure code in Git contains the latest target state and is used for provisioning or maintaining the secondary state.

  • AKS – AKS is provisioned using terraform. The infrastructure code in Git contains the latest target state and is used for provisioning or maintaining the secondary state.

  • Azure SQL – Geo-Replication provided by Azure that ensures the data replication.