Design Decision: Business Continuity and Disaster Recovery Considerations

Every business needs to be operational to generate revenue. The longer a system is down or not functioning, the more revenue that is lost for the business.
At some point in the future, if the system is down long enough, the business becomes a going concern and eventually end.
For some businesses, the outage can be several months, while other business cannot survive after several days.

The key to a good plan is identifying what systems are critical for the business and setting the appropriate mitigation in place.

Here are the questions that you need to answer about Business Continuity and Disaster Recovery:

What Citrix components use Availability Sets or Availability Zones?

• Not all regions support Availability Zones, if they are available in your region, prefer Availability Zones over Availability Sets

• Citrix recommends using the Availability Set or Availability Zones for the following Citrix components:

  • Cloud connector
  • Citrix Gateway
  • StoreFront
  • VDA Hosts

What information do I need to back up?

• Backup anything that is important. Set the backup vault frequency to match the RTO and RPO requirements for the server and set the retention based on corporate data retention policies

• Backups are not automatically copied to the paired region. This task must be done manually or scripted

• Persistent desktops must be backed up

• Golden image machines are to be backed up

What regions should I place my resources in?

• Azure regions are to be selected primarily based on data sovereignty, governance, and compliance

• Place Citrix resources in Azure regions that are close to your users

• Azure regions are paired for disaster recovery/business continuity. Take note of the regional pairs and select the pairs that work best for your users and business continuity plan

• Depending on where your users and data centers are located, one regional pair is a better choice than another regional pair

• When planning for disaster recovery, use the paired region for backups and failover configurations to increase the probability of a successful recovery in the unlikely event of a regional failure

What information should I store in the paired region?

• Identify key servers (recovery tier 0) that absolutely must be up 100% of the time, such as a domain controller, since they are good candidates for replication

• Any servers that are using Azure Site Recovery (ASR) must be pointing to the paired sister region for

• Identify key images/backups for servers that have to be brought online quickly and do not have an automated build available

• Schedule PowerShell jobs to replicate the key images, backups, and snapshots across to the other region

• Regularly export the ARM templates for your configurations and store them in the paired region. This task can be scripted.

What is appropriate to use Azure Site Recovery Replication?

• Any core infrastructure that is considered Recovery Tier 0

• Keep at least one domain controller at the recovery site so the domain passwords are current. That allows the users doing the restore to authenticate to the ASR environment

• Keep at least one Citrix Gateways for remote access into the system

Links to Other Resources

Business continuity and disaster recovery (BCDR): Azure Paired Regions

Enterprise-scale business continuity and disaster recovery

Design Decision: Disaster Recovery Planning