An administrator is designing a new virtual network named VNet1 in an Azure subscription. … — Microsoft Azure Administrator (AZ-104)

An administrator is designing a new virtual network named $VNet1$ in an Azure subscription. The address space for $VNet1$ is configured as $10.12.0.0/22$ . The administrator must configure the following subnets within $VNet1$ to meet specific workload requirements:

* `Subnet-DB` must support at least $124$ database servers.
* `Subnet-App` must support at least $28$ application servers.
* A dedicated subnet for Azure Bastion to enable secure browser-based management.
* A dedicated subnet for an Azure VPN Gateway.

To minimize IP address waste, each subnet must use the smallest possible CIDR block (largest prefix size) that meets its requirements. All subnets must be non-overlapping.

Which subnet configuration meets the requirements?

Subnet-DB: $10.12.0.0/24$ , Subnet-App: $10.12.1.0/26$ , AzureBastionSubnet: $10.12.1.64/26$ , GatewaySubnet: $10.12.1.128/29$ Answer
B
Subnet-DB: $10.12.0.0/25$ , Subnet-App: $10.12.0.128/26$ , AzureBastionSubnet: $10.12.0.192/26$ , GatewaySubnet: $10.12.1.0/29$
C
Subnet-DB: $10.12.0.0/24$ , Subnet-App: $10.12.1.0/26$ , AzureBastionSubnet: $10.12.1.64/27$ , GatewaySubnet: $10.12.1.96/29$
D
Subnet-DB: $10.12.0.0/24$ , Subnet-App: $10.12.1.0/26$ , BastionSubnet: $10.12.1.64/26$ , GatewaySubnet: $10.12.1.128/29$

Answer

The correct subnet configuration is Subnet-DB:

10.12.0.0/24

, Subnet-App:

10.12.1.0/26

, AzureBastionSubnet:

10.12.1.64/26

, GatewaySubnet:

10.12.1.128/29

The correct configuration uses Subnet-DB as

10.12.0.0/24

, Subnet-App as

10.12.1.0/26

, AzureBastionSubnet as

10.12.1.64/26

, and GatewaySubnet as

10.12.1.128/29

. It satisfies all of Azure's sizing and naming constraints: Subnet-DB requires a

/24

block to support

124

database servers (since a

/25

only has

123

usable IPs due to the

5

reserved IPs); Subnet-App requires a

/26

block to support

28

application servers (since a

/27

only has

27

usable IPs); AzureBastionSubnet has the correct name and satisfies the minimum prefix size of

/26

; GatewaySubnet has the correct name and satisfies the minimum prefix size of

/29

; and none of the subnets overlap.

Step-by-Step Solution

Calculate the minimum subnet size for Subnet-DB.

To support

124

database servers, we must add Azure's

5

reserved IP addresses, totaling

129

IP addresses. A

/25

subnet (

128

addresses,

123

usable) is too small, so we must use a

/24

subnet (

256

addresses,

251

usable).

Azure reserves the first four and the last IP address in each subnet.

Calculate the minimum subnet size for Subnet-App.

To support

28

application servers, we add the

5

reserved IPs, requiring

33

IP addresses. A

/27

subnet (

32

addresses,

27

usable) is too small, so we must use a

/26

subnet (

64

addresses,

59

usable).

Azure reserves the first four and the last IP address in each subnet.

Determine Azure Bastion and Gateway subnet requirements.

Azure Bastion requires the subnet name to be exactly 'AzureBastionSubnet' and the prefix size to be at least

/26

. The VPN Gateway subnet must be named 'GatewaySubnet' and must be at least

/29

These are Azure service-specific architecture constraints.

Arrange the subnets within the VNet address space without overlapping.

Aligning the subnets on valid binary boundaries: Subnet-DB at

10.12.0.0/24

, Subnet-App at

10.12.1.0/26

, AzureBastionSubnet at

10.12.1.64/26

, and GatewaySubnet at

10.12.1.128/29

. This fits within the

10.12.0.0/22

range and has no overlaps.

Subnet ranges must be aligned with their prefix sizes and cannot share IP addresses.

Key Concept

Azure Virtual Network subnetting requires accounting for 5 reserved IP addresses per subnet and adhering to system naming and prefix requirements for special subnets such as AzureBastionSubnet (minimum /26) and GatewaySubnet (minimum /29).

Estimated Time:3m 0s

Question

Answer

Step-by-Step Solution

Key Concept

Common Mistakes

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