Merge pull request #310088 from wtnlee/spaceupdate

prmerger-automator[bot] · web-flow · commit b2bd0d1e90fb · 2026-01-05T21:26:17.000Z
hello
diff --git a/articles/virtual-wan/about-nva-hub.md b/articles/virtual-wan/about-nva-hub.md
@@ -114,7 +114,7 @@ NVAs in Virtual WAN are deployed to ensure you always are able to achieve at min
 
 If the total amount of traffic that passes through an NVA at a given time goes above the vendor-specific throughput numbers for the chosen scale unit, events that might cause an NVA instance to be unavailable including but not limited to routine Azure platform maintenance activities or software upgrades can result in service or connectivity disruption. To minimize service disruptions, you should choose the scale unit based on your peak traffic profile and vendor-specific throughput numbers for a particular scale unit as opposed to relying on best-case throughput numbers observed during testing.
 
-### Hub address space
+### <a name="hubspace"></a> Hub address space
 
 Every Virtual WAN hub is deployed with a hub address space. The minimum recommended hub address space is /23. Virtual WAN automatically carves out subnets within the hub to deploy different services within the Virtual WAN hub such as Azure Firewalls, NVAs and gateway connectivity services.
 
diff --git a/articles/virtual-wan/how-to-nva-hub.md b/articles/virtual-wan/how-to-nva-hub.md
@@ -59,7 +59,7 @@ Ensure your Virtual WAN hub has sufficient IP addresses to allow for scalability
 * Add additional IP configurations to your NVA interfaces.
 * Re-size your NVA (increase scale unit).
 
-For more information on how Virtual WAN allocates IP addresses to NVAs in the hub, see [hub address space for NVAs documentation](about-nva-hub.md#hub-address-space).
+For more information on how Virtual WAN allocates IP addresses to NVAs in the hub, see [hub address space for NVAs documentation](about-nva-hub.md#hubspace).
 
 ## Assigning Permissions to Azure Managed Application
 
diff --git a/articles/virtual-wan/hub-settings.md b/articles/virtual-wan/hub-settings.md
@@ -114,7 +114,12 @@ Previously, there wasn't a configuration option for you to use to influence rout
 For more information, see [About virtual hub routing preference](about-virtual-hub-routing-preference.md).
 
 ## <a name = "addressspace"></a>Virtual hub address space
-The recommended address space for a Virtual WAN hub is **/23** or larger. It's important to note that the hub address space **cannot be modified after the hub is created**. To change the hub address space, you must redeploy the virtual hub, which can result in downtime.
+
+The Virtual WAN hub address space **can't be modified after the hub is created**.  Use the following information to select the proper hub address size for your deployment:
+* To accommodate future scalability and architectural needs, while the minimum address space for a Virtual WAN hub is **/24**, it is recommended to specify a **/23 address space** or larger during hub creation.
+* If you are using an Azure Firewall within Virtual WAN, a minimum hub address space of **/22** is required to ensure Azure Firewall is able to allocate sufficient IP addresses to scale to maximum throughput.
+* If you are using Network Virtual Appliances in the Virutal WAN hub, the size of your Virtual WAN hub determines the number of usable IP addresses allocated to NVAs. See [NVA documentation](about-nva-hub.md#hubspace) for the mapping between hub address space and alloctable IP addresses to NVAs.
+  
 
 The Virtual WAN hub automatically assigns subnets from the specified address space to various Azure services, including:
 
@@ -123,10 +128,7 @@ The Virtual WAN hub automatically assigns subnets from the specified address spa
 - [Site-to-site VPN](virtual-wan-site-to-site-portal.md)
 - [Point-to-site VPN](point-to-site-concepts.md)
 - [Azure Firewall](howto-firewall.md)
-
-For scenarios where Network Virtual Appliances (NVAs) are deployed inside the virtual hub, an additional subnet is allocated for the NVA instances. Typically, a **/28 subnet** is assigned for a small number of NVAs. However, if multiple NVAs are provisioned, a **/27 subnet** might be allocated.
-
-To accommodate future scalability and architectural needs, while the minimum address space for a Virtual WAN hub is **/24**, it is recommended to specify a **/23 address space** or larger during hub creation.
+- [Network Virtual Appliances](about-nva-hub.md)
 
 A Virtual WAN hub's address space should **not** overlap with:
 
diff --git a/articles/virtual-wan/virtual-wan-faq.md b/articles/virtual-wan/virtual-wan-faq.md
@@ -430,19 +430,11 @@ The Virtual WAN hub drops routes with an ASN of 0 in the AS-Path. To ensure thes
 Yes. This option is currently available via PowerShell only. The Virtual WAN portal requires that the hubs are in the same resource group as the Virtual WAN resource itself.
 
 ### What is the recommended hub address space during hub creation?
-The recommended address space for a Virtual WAN hub is **/23** or larger. It's important to note that the hub address space **cannot be modified after the hub is created**. To change the hub address space, you must redeploy the virtual hub, which can result in downtime.
 
-The Virtual WAN hub automatically assigns subnets from the specified address space to various Azure services, including:
-
-- Virtual Hub Router
-- ExpressRoute
-- Site-to-site VPN
-- Point-to-site VPN
-- Azure Firewall
-
-For scenarios where Network Virtual Appliances (NVAs) are deployed inside the virtual hub, an additional subnet is allocated for the NVA instances. Typically, a **/28 subnet** is assigned for a small number of NVAs. However, if multiple NVAs are provisioned, a **/27 subnet** might be allocated.
-
-To accommodate future scalability and architectural needs, while the minimum address space for a Virtual WAN hub is **/24**, it is recommended to specify a **/23 address space** or larger during hub creation.
+The Virtual WAN hub address space **can't be modified after the hub is created**. Use the following information to select the proper hub address size for your deployment:
+* To accommodate future scalability and architectural needs, while the minimum address space for a Virtual WAN hub is **/24**, it is recommended to specify a **/23 address space** or larger during hub creation.
+* If you are using an Azure Firewall within Virtual WAN, a minimum hub address space of **/22** is required to ensure Azure Firewall is able to allocate sufficient IP addresses to scale to maximum throughput.
+* If you are using Network Virtual Appliances in the Virutal WAN hub, the size of your Virtual WAN hub determines the number of usable IP addresses allocated to NVAs. See [NVA documentation](about-nva-hub.md#hubspace) for the mapping between hub address space and alloctable IP addresses to NVAs.
 
 ### Is there support for IPv6 in Virtual WAN?
 
