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It is not possible to deploy an Azure ExpressRoute Gateway with high availability and resiliency by distributing it across multiple availability zones in the Canada East Region. This is because the Canada East Region is not currently listed as a supported region for zone-redundant ExpressRoute gateways
The ability to deploy zone-redundant ExpressRoute gateways is limited to specific regions that support Azure availability zones. According to the available information, the supported regions for zone-redundant ExpressRoute gateways include:
- Central US
- East US
- East US 2
- West US 2
- France Central
- North Europe
- UK South
- West Europe
- Japan East
- Southeast Asia
- Australia East
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