Takes the ExpressRoute gateway out of the data path so on-premises traffic reaches VMs directly with the lowest latency. It needs Ultra Performance, ErGw3Az or ErGwScale of 10+ scale units, and does not make failover quicker.
Also called FastPath.
Read more: Microsoft Learn
In the Ultra Transcenders books
Each book explains ExpressRoute FastPath in context, with comparison tables and the common traps.
Terms in this definition
- ExpressRoute gateway
Connects a virtual network to an ExpressRoute circuit from inside GatewaySubnet. Only one is allowed per VNet, and VPN traffic needs a separate gateway.
- PATH
Parent-child hierarchies in DAX rely on this function. For each row it builds one delimited text value listing the IDs of the row's ancestors, top level first and ending with the row's own ID, which PATHITEM, PATHLENGTH and friends can then pick apart.
- Virtual machines
Infrastructure-as-a-service compute giving complete control of the operating system, making it a fit for lift-and-shift moves and for software relying on OS-level pieces like COM.
- Ultra Performance
An ExpressRoute gateway SKU, not zone-redundant, that supports FastPath. Its greater throughput does not make failure detection any quicker.
- ErGw3Az
Zone-redundant counterpart to the Ultra Performance ExpressRoute gateway, with FastPath support.
- ErGwScale
Scalable ExpressRoute gateway SKU, zone-redundant, built from 1-Gbps scale units numbering 1 to 40, either fixed or autoscaled. FastPath requires 10 units or more.
Related terms
- ErGw1Az
ExpressRoute gateway SKU deployed across availability zones, offering roughly 1 Gbps like Standard, without FastPath support.
- ErGw2Az
The zone-redundant equivalent of the High Performance ExpressRoute gateway; FastPath isn't available on it.
- High Performance
An ExpressRoute gateway SKU that is not zone-redundant (non-AZ) and does not offer FastPath.