ExpressRoute gateway

In the Ultra Transcenders books

AZ-700

Each book explains ExpressRoute gateway in context, with comparison tables and the common traps.

Terms in this definition

• VNet

  A private network belonging to a single subscription and region and covering all of that region's availability zones. A VM can only use a VNet located in the same region.

• ExpressRoute circuit

  The logical link between on-premises and Microsoft, provided by a connectivity partner or through ExpressRoute Direct. A service key identifies it, and it carries both Microsoft and private peering.

• GatewaySubnet

  The subnet reserved for ExpressRoute or VPN gateways, which should be at least /27.

• VPN

  Traffic sent through an encrypted tunnel across a public network, as in a site-to-site connection to a VPN gateway in an Azure GatewaySubnet.

Related terms

• AZ SKU

  Any VPN or ExpressRoute gateway SKU carrying the AZ suffix (VpnGw1AZ to 5AZ, ErGw1Az to 3Az). In regions with availability zones its instances spread across zones; in other regions it deploys regionally, becoming zone-redundant once zones are introduced there.

• 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.

• 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.

• ExpressRoute and S2S VPN coexistence

  Running a route-based VPN gateway (VpnGw1 or above, never Basic) alongside the ExpressRoute gateway in one VNet, sharing a GatewaySubnet of at least /27; the VPN acts as backup or links other sites.

• ExpressRoute FastPath

  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.

• ExpressRoute gateway Standard SKU

  ExpressRoute gateway SKU of around 1 Gbps that is neither zone-redundant nor FastPath-capable.