Single Availability Zone Amazon WorkSpaces Personal Deployment: A Practical Approach
This post walks through the considerations for a WorkSpaces deployment into a single availability zone
Asriel A.
Amazon Employee
Published Apr 21, 2025
When deploying Amazon WorkSpaces, organizations often face the challenge of balancing AWS's architectural requirements with practical business needs. While AWS requires WorkSpaces to be configured across multiple Availability Zones (AZs), there are compelling reasons to concentrate WorkSpaces deployments in a single AZ. This article explores a practical approach to achieving this, along with important considerations for implementation.
Understanding the fundamental architecture of WorkSpaces is crucial before implementing any deployment strategy. WorkSpaces operate on a 1:1 mapping, meaning each user is assigned to a specific WorkSpace instance. Importantly, these instances don't have built-in high availability features, and if an AZ fails, affected users cannot access their WorkSpaces regardless of multi-AZ configuration. Additionally, cross-AZ data transfer incurs costs that can significantly impact operational expenses.
Organizations might consider single-AZ deployment for several reasons. Common scenarios include situations where backend resources such as databases and file shares exist in a single AZ, when there's a need to minimize cross-AZ data transfer costs, or when specific network latency targets must be met.
To achieve a single-AZ deployment, we can use one of two methods:
Method 1: CIDR Block Configuration
- Create your primary subnet in your target AZ with sufficient IP space (e.g., /22 or larger)
- Create a secondary subnet in another AZ with minimal IP space (e.g., /28)
- Select these subnets when registering your Directory with the WorkSpaces Service
- When creating WorkSpaces, they will naturally deploy to the subnet with available IP space
Method 2: ENI Management
- Create two subnets of equal size in different AZs
- In the non-preferred AZ, consume available ENIs using other AWS services (like EC2 instances)
- When WorkSpaces are created, they will automatically deploy to the AZ with available ENIs
- Monitor and maintain ENI utilization to ensure continued deployment to your preferred AZ
A crucial point often overlooked is that the Directory Service can operate in subnets different from the WorkSpaces themselves. This means you can maintain multi-AZ compliance for your Directory Service while concentrating WorkSpaces in your preferred AZ. The only requirement is maintaining network connectivity between the WorkSpaces and Directory Service subnets.
Implementation requires careful attention to networking details. Proper configuration of routing tables, security groups, and NAT Gateways in your target AZ is essential. Cost optimization should be a key focus, implemented through features like AutoStop for unused WorkSpaces and the Amazon WorkSpaces Cost Optimizer. Regular monitoring through CloudWatch metrics, auditing WorkSpace distribution, and tracking cost savings from reduced cross-AZ traffic are vital parts of managing this deployment strategy.
While this approach isn't officially supported by AWS, it acknowledges the reality that individual WorkSpaces don't provide high availability, and multi-AZ configuration doesn't offer automatic failover. The strategy represents a practical solution for organizations with specific requirements around AZ placement and cost optimization. Best practices include maintaining thorough documentation of your deployment approach, clear communication with stakeholders about the design choice, and staying current with Amazon WorkSpaces service updates.
The key to successful implementation lies in understanding that WorkSpaces' multi-AZ requirement doesn't provide true high availability for individual users, making single-AZ deployment a viable option for many use cases. This deployment strategy demonstrates how understanding the underlying architecture allows for innovative solutions that meet both technical and business requirements while optimizing costs and performance.
Organizations implementing this approach should maintain clear documentation of their design decisions, establish regular monitoring practices, and stay informed about AWS service updates that might affect their deployment. By acknowledging both AWS's architectural requirements and real-world business needs, this solution provides a practical path forward for organizations looking to optimize their WorkSpaces deployment while maintaining service functionality.
Any opinions in this post are those of the individual author and may not reflect the opinions of AWS.