Merge pull request #289918 from ramandhillon84/master

Adding private IP address blocks to related articles

Author: JamesJBarnett

articles/virtual-network/ip-services/ip-services-overview.md

@@ -1,18 +1,18 @@
 ---
-title: What is Azure Virtual Network IP Services?
-description: Overview of Azure Virtual Network IP Services. Learn how IP services work and how to use IP resources in Azure.
+title: What is Azure virtual network IP Services?
+description: Overview of Azure virtual network IP Services. Learn how IP services work and how to use IP resources in Azure.
 author: mbender-ms
 ms.author: mbender
-ms.date: 08/24/2023
+ms.date: 11/05/2024
 ms.service: azure-virtual-network
 ms.subService: ip-services
 ms.topic: overview
 ms.custom: template-overview
 ---
 
-# What is Azure Virtual Network IP Services?
+# What is Azure Virtual network IP Services?
 
-IP services are a collection of IP address related services that enable communication in an Azure Virtual Network. Public and private IP addresses are used in Azure for communication between resources. The communication with resources can occur in a private Azure Virtual Network and the public Internet.
+IP services are a collection of IP address related services that enable communication in an Azure virtual network. Public and private IP addresses are used in Azure for communication between resources. The communication with resources can occur in a private Azure virtual network and the public Internet.
 
 IP services consist of:
 
@@ -76,7 +76,13 @@ Private IPs allow communication between resources in Azure. Azure assigns privat
 
 Some of the resources that you can associate a private IP address with are:
 
-* Virtual machines
+* Network Interface (for Virtual machines, Virtual Machine Scale Sets, container pods ...)
+    
+    * Network Interfaces can contain one primary and multiple secondary IP configurations. 
+
+    * Each primary IP configuration must be a single IP address (a /32 IPv4 address or a /128 IPv6 address).
+
+    * Secondary IP configurations can be a single IP address OR a block of IP addresses (*in preview*). Only IPv4 addresses of block size of /28 are available today for associating with a secondary IP configuration.
 
 * Internal load balancers
 

articles/virtual-network/ip-services/media/virtual-network-private-ip-addresses-blocks-portal/add-dynamic-ip-prefix-config-expand.png

@@ -4,7 +4,7 @@ titlesuffix: Azure Virtual Network
 description: Learn about private IP addresses in Azure.
 author: mbender-ms
 ms.author: mbender
-ms.date: 12/01/2023
+ms.date: 11/05/2024
 ms.service: azure-virtual-network
 ms.subservice: ip-services
 ms.topic: conceptual
@@ -42,6 +42,8 @@ There are two methods in which a private IP address is given:
 
 Azure assigns the next available unassigned or unreserved IP address in the subnet's address range. While this is normally the next sequentially available address, there's no guarantee that the address will be the next one in the range. For example, if addresses 10.0.0.4-10.0.0.9 are already assigned to other resources, the next IP address assigned is most likely 10.0.0.10. However, it could be any address between 10.0.0.10 and 10.0.0.254. If a specific Private IP address is required for a resource, you should use a static private IP address.
 
+A private IP address prefix allocation is only successful when the full unallocated block of IP addresses is available. For example, only a valid /28 IPv4 address block will result in a successful prefix allocation.
+
 Dynamic is the default allocation method. Once assigned, dynamic IP addresses are released if a network interface is:
 
 * Deleted
@@ -65,9 +67,14 @@ To assign the network interface to a different subnet, you change the allocation
 > [!NOTE]
 > When requesting a private IP address, the allocation is not deterministic or sequential. There are no guarantees the next allocated IP address will utilize the next sequential IP address or use previously deallocated addresses. If a specific Private IP address is required for a resource, you should consider using a static private IP address.
     
-## Virtual machines
+## Virtual machine network interfaces
+
+One or more private IP addresses are assigned to one or more **network interfaces** of a Virtual Machine. Network interfaces are assigned to a [Windows](/azure/virtual-machines/windows/overview?toc=%2fazure%2fvirtual-network%2ftoc.json) or [Linux](/azure/virtual-machines/linux/overview?toc=%2fazure%2fvirtual-network%2ftoc.json) virtual machine, and enable connectivity with other resources within and outside the Virtual Network. 
 
-One or more private IP addresses are assigned to one or more **network interfaces**. The network interfaces are assigned to a [Windows](/azure/virtual-machines/windows/overview?toc=%2fazure%2fvirtual-network%2ftoc.json) or [Linux](/azure/virtual-machines/linux/overview?toc=%2fazure%2fvirtual-network%2ftoc.json) virtual machine. You can specify the allocation method as either dynamic or static for each private IP address.
+Network interfaces are configured with private IP addresses for communication within the Azure virtual network and other Azure resources, and can optionally be configured with public IP addresses for communication outside the Azure (e.g. Internet, customer on-premises).
+A network interface has one primary IP configuration associated with them and an option to attach zero or more secondary private IP configurations. For the total count of private IP configurations on a network interface allowed in your subscription, see [Azure limits](../../azure-resource-manager/management/azure-subscription-service-limits.md?toc=%2fazure%2fvirtual-network%2ftoc.json#azure-resource-manager-virtual-networking-limits). The primary IP configuration on the network interface must have a single IP address (a /32 IPv4 address or a /128 IPv6 address) attached to it, while the secondary IP configurations can have either a single IP address or a block of IP addresses (*in preview*) attached to them. The only allowed blocks are IPv4 addresses of size /28 today.
+
+You can specify the allocation method as either dynamic or static for each private IP address.
 
 ### Internal DNS hostname resolution (for virtual machines)
 
@@ -117,4 +124,6 @@ The limits on IP addressing are found in the full set of [limits for networking]
 
 * Learn about [Public IP Addresses in Azure](public-ip-addresses.md)
 
-* [Deploy a VM with a static private IP address using the Azure portal](./virtual-networks-static-private-ip-arm-pportal.md)
+* [Deploy a VM with a static private IP address using the Azure portal](./virtual-networks-static-private-ip-arm-pportal.md)
+
+* [Deploy a VM that uses private IP address blocks for a larger scale using the Azure portal](./virtual-network-private-ip-address-blocks-portal.md)

articles/virtual-network/ip-services/media/virtual-network-private-ip-addresses-blocks-portal/add-dynamic-ip-prefix-config.png

@@ -146,6 +146,8 @@ items:
           href: virtual-network-multiple-ip-addresses-powershell.md
         - name: Azure CLI
           href: virtual-network-multiple-ip-addresses-cli.md
+      - name: Assign private IP address prefixes to VM
+        href: virtual-network-private-ip-address-blocks-portal.md
       - name: Virtual machine scale set with IPv6
         href: ipv6-virtual-machine-scale-set.md
       - name: Configure DHCPv6 for Linux VMs
@@ -200,4 +202,4 @@ items:
   - name: Pricing calculator
     href: https://azure.microsoft.com/pricing/calculator/
   - name: Stack Overflow
-    href: https://stackoverflow.com/questions/tagged/azure-virtual-network
+    href: https://stackoverflow.com/questions/tagged/azure-virtual-network