ExpressRoute Scalable Gateway #azure #networking

Key Concepts

• ExpressRoute Gateway: A service providing private network connections between on-premises infrastructure and Azure.
• SKU (Stock Keeping Unit): A specific configuration of a product, in this case, defining throughput capacity for the ExpressRoute Gateway.
• Scale Unit: A modular unit of capacity for the new ExpressRoute Gateway, providing 1 Gbit/s throughput.
• Zone Redundancy: Distributing resources across multiple availability zones to improve resilience.
• Throughput: The amount of data transferred over a network connection in a given time, measured in Gbit/s.
• Automatic Scaling: Dynamically adjusting the number of scale units based on demand.

Introduction of the ExpressRoute Gateway Scalable SKU

The video introduces a new offering for the Azure ExpressRoute Gateway: a scalable SKU. Previously, ExpressRoute Gateways were offered in fixed throughput SKUs – 1, 2, and 10 Gbit/s. These older SKUs, while zone redundant, were limited to a maximum throughput of 10 Gbit/s. The new scalable SKU addresses this limitation by introducing a more flexible and cost-effective approach to capacity management.

Functionality of Scale Units

The core of the new SKU lies in the concept of “scale units.” Users now configure a minimum and maximum number of these scale units. Each scale unit provides 1 Gbit/s of throughput, along with corresponding packet processing capacity and connection limits. This granular control allows for precise capacity allocation. The speaker clarifies that setting the minimum and maximum scale units to the same value effectively creates a fixed capacity, similar to the previous SKUs, but with the added benefit of being dynamically adjustable.

Automatic Scaling and Cost Optimization

The primary advantage of the scalable SKU is its automatic scaling capability. When operating in automatic mode, the gateway monitors key metrics – throughput, CPU utilization, and packet flow – and dynamically adjusts the number of active scale units. If demand increases, the gateway automatically provisions more instances (scale units) to maintain performance. Conversely, when utilization is low, it reduces the number of instances, minimizing costs. Crucially, users are billed only for the number of scale units actively provisioned, leading to significant cost savings when demand fluctuates.

Seamless Migration

The video highlights the ease of transitioning from existing zone-redundant SKUs to the new scalable SKU. The speaker explicitly states that this migration can be performed without any downtime, simplifying the upgrade process for existing ExpressRoute users.

Real-World Application & Benefits

This new SKU is particularly beneficial for organizations with variable network traffic patterns. For example, a company running batch processing jobs overnight might experience high throughput during those hours but low throughput during the day. The automatic scaling feature ensures sufficient capacity during peak times while minimizing costs during off-peak times. This contrasts with the previous fixed SKU model, where users would have to over-provision to accommodate peak demand, resulting in wasted resources.

Notable Quote

“I can really easily switch from the zone redundant SKUs to the gateway scale skew without any downtime.” – This statement emphasizes the ease of adoption and minimal disruption associated with the new offering.

Technical Specifications (Implied)

While not explicitly stated, the video implies the following:

• Throughput per Scale Unit: 1 Gbit/s
• Scaling Granularity: 1 Gbit/s increments
• Monitoring Metrics: Throughput, CPU Utilization, Packet Flow
• Billing Model: Pay-as-you-go, based on active scale units.

Conclusion

The ExpressRoute Gateway scalable SKU represents a significant improvement in flexibility and cost-efficiency for Azure ExpressRoute users. By introducing scale units and automatic scaling, Microsoft empowers organizations to dynamically adjust their network capacity to meet fluctuating demands, optimizing both performance and expenditure. The seamless migration path from existing SKUs further enhances the appeal of this new offering.