Merge pull request #239496 from asudbring/vnet-old-review-2

May VNET article review - VNET peering overview

Author: prmerger-automator[bot]

articles/virtual-network/virtual-network-peering-overview.md

@@ -7,26 +7,33 @@ author: asudbring
 ms.service: virtual-network
 ms.topic: conceptual
 ms.workload: infrastructure-services
-ms.date: 07/10/2022
+ms.date: 05/28/2023
 ms.author: allensu
 #customer intent: As a cloud architect, I need to know how to use virtual network peering for connecting virtual networks. This will allow me to design connectivity correctly, understand future scalability options, and limitations.
 ---
+
 # Virtual network peering
 
 Virtual network peering enables you to seamlessly connect two or more [Virtual Networks](virtual-networks-overview.md) in Azure. The virtual networks appear as one for connectivity purposes. The traffic between virtual machines in peered virtual networks uses the Microsoft backbone infrastructure. Like traffic between virtual machines in the same network, traffic is routed through Microsoft's *private* network only.
 
 Azure supports the following types of peering:
 
 * **Virtual network peering**: Connecting virtual networks within the same Azure region.
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 * **Global virtual network peering**: Connecting virtual networks across Azure regions.
 
 The benefits of using virtual network peering, whether local or global, include:
 
 * A low-latency, high-bandwidth connection between resources in different virtual networks.
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 * The ability for resources in one virtual network to communicate with resources in a different virtual network.
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 * The ability to transfer data between virtual networks across Azure subscriptions, Azure Active Directory tenants, deployment models, and Azure regions.
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 * The ability to peer virtual networks created through the Azure Resource Manager.
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 * The ability to peer a virtual network created through Resource Manager to one created through the classic deployment model. To learn more about Azure deployment models, see [Understand Azure deployment models](../azure-resource-manager/management/deployment-models.md?toc=%2fazure%2fvirtual-network%2ftoc.json).
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 * No downtime to resources in either virtual network when creating the peering, or after the peering is created.
 
 Network traffic between peered virtual networks is private. Traffic between the virtual networks is kept on the Microsoft backbone network. No public Internet, gateways, or encryption is required in the communication between the virtual networks.
@@ -44,16 +51,20 @@ When you configure virtual network peering, either open or close the network sec
 
 ## Resize the address space of Azure virtual networks that are peered
 
-You can resize the address space of Azure virtual networks that are peered without incurring any downtime on the currently peered address space. This feature is useful when you need to resize the virtual network's address space after scaling your workloads. After resizing the address space, all that is required is for peers to be synced with the new address space changes. Resizing works for both IPv4 and IPv6 address spaces. 
+You can resize the address space of Azure virtual networks that are peered without incurring any downtime on the currently peered address space. This feature is useful when you need to resize the virtual network's address space after scaling your workloads. Once the address space is resized, peers must sync with the new address space changes. Resizing works for both IPv4 and IPv6 address spaces. 
 
 Addresses can be resized in the following ways:
 
 - Modifying the address range prefix of an existing address range (For example changing 10.1.0.0/16 to 10.1.0.0/18)
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 - Adding address ranges to a virtual network
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 - Deleting address ranges from a virtual network
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 - Resizing of address space is supported cross-tenant
 
 Synching of virtual network peers can be performed through the Azure portal or with Azure PowerShell. We recommend that you run sync after every resize address space operation instead of performing multiple resizing operations and then running the sync operation. To learn how to update the address space for a peered virtual network, see [Updating the address space for a peered virtual network](./update-virtual-network-peering-address-space.md).
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 > [!IMPORTANT]
 > This feature doesn't support scenarios where the virtual network to be updated is peered with: 
 > * A classic virtual network
@@ -77,7 +88,7 @@ When you configure both options for virtual network interconnectivity, the traff
 
 You can also configure the gateway in the peered virtual network as a transit point to an on-premises network. In this case, the virtual network that is using a remote gateway can't have its own gateway. A virtual network could have only one gateway, the gateway should be either local or remote gateway in the peered virtual network as shown in the following diagram:
 
-![virtual network peering transit](./media/virtual-networks-peering-overview/local-or-remote-gateway-in-peered-virual-network.png)
+:::image type="content" source="./media/virtual-networks-peering-overview/local-or-remote-gateway-in-peered-virual-network.png" alt-text="Diagram of virtual network peering transit.":::
 
 Both virtual network peering and global virtual network peering support gateway transit.
 
@@ -98,6 +109,7 @@ You can also try the [Troubleshoot virtual network peering issues](virtual-netwo
 The following constraints apply only when virtual networks are globally peered:
 
 * Resources in one virtual network can't communicate with the front-end IP address of a Basic Load Balancer (internal or public)  in a globally peered virtual network.
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 * Some services that use a Basic load balancer don't work over global virtual network peering. For more information, see [What are the constraints related to Global VNet Peering and Load Balancers?](virtual-networks-faq.md#what-are-the-constraints-related-to-global-vnet-peering-and-load-balancers).
 
 For more information, see [Requirements and constraints](virtual-network-manage-peering.md#requirements-and-constraints). To learn more about the supported number of peerings, see [Networking limits](../azure-resource-manager/management/azure-subscription-service-limits.md?toc=%2fazure%2fvirtual-network%2ftoc.json#azure-resource-manager-virtual-networking-limits).
@@ -110,7 +122,7 @@ To learn about permissions required to create a virtual network peering, see [Pe
 
 There's a nominal charge for ingress and egress traffic that uses a virtual network peering connection. For more information, see [Virtual Network pricing](https://azure.microsoft.com/pricing/details/virtual-network).
 
-Gateway Transit is a peering property that enables a virtual network to utilize a VPN/ExpressRoute gateway in a peered virtual network. Gateway transit works for both cross premises and network-to-network connectivity. Traffic to the gateway (ingress or egress) in the peered virtual network incurs virtual network peering charges on the spoke VNet (or non-gateway VNet). For more information, see [VPN Gateway pricing](https://azure.microsoft.com/pricing/details/vpn-gateway/) for VPN gateway charges and ExpressRoute Gateway pricing for ExpressRoute gateway charges.
+Gateway Transit is a peering property that enables a virtual network to utilize a VPN/ExpressRoute gateway in a peered virtual network. Gateway transit works for both cross premises and network-to-network connectivity. Traffic to the gateway (ingress or egress) in the peered virtual network incurs virtual network peering charges on the spoke virtual network (or virtual network without a VPN gateway). For more information, see [VPN Gateway pricing](https://azure.microsoft.com/pricing/details/vpn-gateway/) for VPN gateway charges and ExpressRoute Gateway pricing for ExpressRoute gateway charges.
 
 >[!NOTE]
 > A previous version of this document stated that virtual network peering charges would not apply on the spoke VNet (or non-gateway VNet) with Gateway Transit. It now reflects accurate pricing per the pricing page.
@@ -127,5 +139,7 @@ Gateway Transit is a peering property that enables a virtual network to utilize
     |                                   |[Different](create-peering-different-deployment-models-subscriptions.md)|
 
 * To learn how to create a hub and spoke network topology, see [Hub-spoke network topology in Azure](/azure/architecture/reference-architectures/hybrid-networking/hub-spoke?toc=%2fazure%2fvirtual-network%2ftoc.json).
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 * To learn about all virtual network peering settings, see [Create, change, or delete a virtual network peering](virtual-network-manage-peering.md).
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 * For answers to common virtual network peering and global virtual network peering questions, see [VNet Peering](virtual-networks-faq.md#vnet-peering).