Manage network resources in Azure Stack Hub

MAC address pool

Azure Stack Hub uses a static MAC address pool to automatically generate and assign MAC address to virtual machines (VMs). This MAC address pool is automatically generated during deployment and uses the following range:

  • StartMacAddress: 00-1D-D8-B7-00-00
  • EndMacAddress: 00-1D-D8-F4-FF-FF

Note

This MAC address pool is the same across each Azure Stack Hub system and is not configurable.

Depending on how the virtual networks connect with existing corporate networks, you may expect duplicated MAC addresses of VMs.

More information can be found about MAC address pool utilization using the cmdlet Get-AzsMacAddressPool in the Azure Stack Hub administrator PowerShell module.

View public IP address consumption in Azure Stack Hub

As a cloud administrator, you can view:

  • The number of public IP addresses that have been allocated to tenants.
  • The number of public IP addresses that are still available for allocation.
  • The percentage of public IP addresses that have been allocated in that location.

The Public IP pools usage tile shows the number of public IP addresses consumed across public IP address pools. For each IP address, the tile shows usage for tenant IaaS VM instances, fabric infrastructure services, and public IP address resources that were explicitly created by tenants.

The purpose of the tile is to give Azure Stack Hub operators a sense of the number of public IP addresses used in this location. The number helps administrators determine whether they're running low on this resource.

The Public IP addresses menu item under Tenant Resources lists only those public IP addresses that have been explicitly created by tenants. You can find the menu item on the Resource providers -> Network pane. The number of Used public IP addresses on the Public IP pools usage tile is always different from (larger than) the number on the Public IP Addresses tile under Tenant Resources.

View the public IP address usage information

To view the total number of public IP addresses that have been consumed in the region:

  1. In the Azure Stack Hub administrator portal, select All services. Then, under the ADMINISTRATION category, select Network.

  2. The Network pane displays the Public IP pools usage tile in the Overview section.

    Network Resource Provider pane in Azure Stack Hub administrator portal

The Used number represents the number of assigned public IP addresses from public IP address pools. The Free number represents the number of public IP addresses from public IP address pools that haven't been assigned and are still available. The % Used number represents the number of used or assigned addresses as a percentage of the total number of public IP addresses in public IP address pools in that location.

View the public IP addresses that were created by tenant subscriptions

Select Public IP addresses under Tenant Resources. Review the list of public IP addresses explicitly created by tenant subscriptions in a specific region.

Tenant public IP addresses in Azure Stack Hub administrator portal

You might notice that some public IP addresses that have been dynamically allocated appear in the list. However, an address hasn't been associated with them yet. The address resource has been created in the Network Resource Provider, but not yet in the Network Controller.

The Network Controller doesn't assign an address to the resource until it binds to an interface, a network interface card (NIC), a load balancer, or a virtual network gateway. When the public IP address binds to an interface, the Network Controller allocates an IP address. The address appears in the Address field.

View the public IP address information summary table

In different cases, public IP addresses are assigned that determine whether the address appears in one list or another.

Public IP address assignment case Appears in usage summary Appears in tenant public IP addresses list
Unassigned dynamic public IP address (temporary). No Yes
Dynamic public IP address assigned to a NIC or load balancer. Yes Yes
Static public IP address assigned to a tenant NIC or load balancer. Yes Yes
Static public IP address assigned to a fabric infrastructure service endpoint. Yes No
Public IP address implicitly created for the virtual network. This public IP is created only after the first standalone VM (VM without public IP or load balancer assigned) is connected to the virtual network. This NAT IP address ensures the outbound connectivity for any standalone VM connected to the virtual network. To release this public IP usage from the pool is necessary to disconnect all the VMs from the virtual network and remove the virtual network. Yes No

Next steps

Manage Storage Accounts in Azure Stack Hub