A common DNS virtual service for TCP and UDP requests can be configured using the Edit Virtual Service option in the NSX Advanced Load Balancer UI. This virtual service responds to both types of requests, namely TCP and UDP.

Run the following steps to configure a common DNS virtual service that will respond to TCP and UDP requests:

  1. Login to the NSX Advanced Load Balancer user interface. Navigate to Applications > Virtual Services. Choose the desired virtual service and click the edit icon (the pencil icon). To create a new virtual service, see Creating a Virtual Service in Basic Setup section in VMware NSX Advanced Load BalancerConfiguration guide.

  2. In the Settings tab, choose System-DNS from the Application Profile drop-down menu under the Profiles section. For TCP/UDP Profile, select System-UDP-Per-Pkt from the drop-down menu.

  3. In the Service Port section, click Switch to Advanced link.

  4. Click Add Port and set the value for Port Min as 53 and Port Max as 53.

  5. Select the Override TCP/UDP check box and select System-TCP-Proxy from the drop-down menu. Click Save.

Checking logs using NSX Advanced Load Balancer UI

To confirm DNS requests changes, logs for the DNS virtual service can be checked using the NSX Advanced Load Balancer user interface. Follow the below-mentioned steps to access the logs for the virtual service:

  1. Navigate to Applications > Virtual Services, click the virtual service name and navigate to the Logs tab.

  2. Observe that the same virtual service responds to TCP and UDP requests coming from a client IP address for DNS request type.