AZ-700 Question 30
Single answerYou have created a new Azure Virtual Network (vNet-Prod) and set up a Site-to-Site VPN to your on-premises environment. You want all virtual machines in vNet-Prod to resolve internal domain names (example.mycorp.local) using your on-premises DNS servers (10.1.0.5 and 10.1.0.6). Which of the following actions must you take to properly configure DNS settings for vNet-Prod so that new and existing VMs can use your on-premises DNS servers for name resolution?
- A
A. Change each VM� NIC settings to use 10.1.0.5 and 10.1.0.6 as DNS servers, leaving the vNet default DNS options as-is.
- B
B. Edit the DNS server addresses under vNet-Prod� DNS settings to use 10.1.0.5 and 10.1.0.6, then restart or reapply IP configurations on each VM to pick up the new DNS settings.
- C
C. Configure a conditional forwarder in Azure DNS to forward requests for the on-premises domain to 10.1.0.5 and 10.1.0.6.
- D
D. Modify the vNet� DHCP options to direct all VMs to the on-premises DNS servers, without changing each VM� configuration.
Show answer and explanation
Correct answer: B
Explanation
When using custom DNS with Azure Virtual Networks, you specify your DNS server IP addresses at the vNet level under 'DNS servers.' This ensures that any VM in the virtual network automatically picks up the correct DNS settings. After making changes to the vNet DNS configuration, you should restart or reapply network settings on existing VMs to refresh their DNS configuration. Refer to Microsoft� documentation at https://learn.microsoft.com/azure/virtual-network/virtual-networks-name-resolution-for-vms-and-role-instances for best practices on name resolution in Azure.
- A. Incorrect.
Option A: Incorrect. While manually configuring each VM� NIC DNS settings works in isolated scenarios, it does not scale well and can lead to inconsistent configurations. Microsoft recommends configuring DNS at the Virtual Network level so that new (and existing) VMs inherit the correct settings automatically.
- B. Correct.
Option B: Correct. To enable VMs to use on-premises DNS servers for name resolution, you must specify custom DNS servers in the virtual network settings. After changing the DNS servers in the vNet settings, you need to restart VMs or reapply IP configurations so they receive the new DNS addresses via DHCP from Azure.
- C. Incorrect.
Option C: Incorrect. Configuring a conditional forwarder in Azure DNS private zones applies if you are using Azure DNS for zone hosting. However, simply adding a conditional forwarder is not sufficient unless you have a private DNS zone in Azure that delegates queries. The scenario requires specifying the on-prem addresses at the vNet level, not just a forwarder in Azure DNS.
- D. Incorrect.
Option D: Incorrect. Azure Virtual Networks do not provide direct DHCP option configuration in the same way an on-premises DHCP server does. DNS server settings for Azure VMs are centrally managed via the virtual network, not via a separate DHCP scope configuration.