An Azure subscription contains a virtual network named vnet-manufacturing that has an addr… — Microsoft Azure Administrator (AZ-104)

An Azure subscription contains a virtual network named $vnet-manufacturing$ that has an address space of $10.80.0.0/21$ . You are configuring the subnets for this virtual network to support hybrid connectivity and a new application workload. The configuration must meet the following requirements:
- Create a subnet named $GatewaySubnet$ to support a VPN gateway.
- Create a subnet named $snet-app$ to host 28 virtual machines.
- Minimize the address space allocated to each subnet.

Which two subnets should you create to meet the requirements? Select two.

$GatewaySubnet$ with the address range $10.80.0.0/29$ Answer
B
$GatewaySubnet$ with the address range $10.80.0.0/30$
$snet-app$ with the address range $10.80.1.0/26$ Answer
D
$snet-app$ with the address range $10.80.1.0/27$
E
$snet-app$ with the address range $10.80.1.0/28$

Answer

The correct subnets to create are GatewaySubnet with the address range 10.80.0.0/29 and snet-app with the address range 10.80.1.0/26.

The GatewaySubnet must be at least /29 to support Azure VPN Gateway. A /29 subnet is the smallest valid subnet size that meets this requirement. For the snet-app subnet, hosting 28 virtual machines requires a total of 33 IP addresses (

28 + 5 = 33

) due to the 5 IP addresses reserved by Azure in each subnet. A /27 subnet provides 32 addresses (27 usable), which is not enough. A /26 subnet provides 64 addresses (59 usable), which is the smallest subnet size that can support the workload.

Step-by-Step Solution

Determine the minimum size of the GatewaySubnet.

The GatewaySubnet must be configured with a prefix length of /29 or larger.

Azure VPN Gateway requires a dedicated subnet named GatewaySubnet, and Azure mandates a minimum size of /29 for this subnet. Therefore, a /29 subnet represents the smallest allocation.

Calculate the minimum subnet size for snet-app to host 28 virtual machines.

A subnet with a /26 prefix length is required.

Azure reserves 5 IP addresses in every subnet (the first four and the last one). To host 28 virtual machines, the subnet must have a total capacity of at least 33 IP addresses (

28 + 5 = 33

). A /27 subnet provides only 32 IP addresses (27 usable), whereas a /26 subnet provides 64 IP addresses (59 usable).

Key Concept

Azure subnet sizing and IP address reservation rules, including the minimum size requirement for a GatewaySubnet and the 5 reserved IP addresses per subnet.

Question

Answer

Step-by-Step Solution

Key Concept

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