Validate a domain for direct routing

This article describes the process of validating domain name ownership by using the Azure portal.

A fully qualified domain name (FQDN) consists of two parts: host name and domain name. For example, if your session border controller (SBC) name is, then sbc1 is the host name and is the domain name. If an SBC has an FQDN of, then acs is the host name and is the domain name.

To use direct routing in Azure Communication Services, you need to validate that you own the domain part of your SBC FQDN. After that, you can configure the SBC FQDN and port number and then create voice routing rules.

When you're verifying the domain name portion of the SBC FQDN, keep in mind that the * and * domain names aren't supported. For example, if you have two domain names, and, use as the SBC name.

If you're using a subdomain, make sure that this subdomain is also added and verified. For example, if you want to use, you need to register

Add a new domain name

  1. Open the Azure portal and go to your Communication Services resource.
  2. On the left pane, under Voice Calling - PSTN, select Direct routing.
  3. On the Domains tab, select Connect domain.
  4. Enter the domain part of the SBC FQDN.
  5. Reenter the domain name.
  6. Select Confirm, and then select Add.

Screenshot of adding a custom domain.

Verify domain ownership

  1. On the Domains tab, select Verify next to the new domain that you created.

  2. The Azure portal generates a value for a TXT record. Add that record to your domain's registrar or DNS hosting provider with the provided value.

    Screenshot of verifying a custom domain.

    It might take up to 30 minutes for a new DNS record to propagate on the internet.

  3. Select Next. If you set up everything correctly, Domain status should change to Verified next to the added domain.

    Screenshot of a verified domain.

Remove a domain from Azure Communication Services

If you want to remove a domain from your Azure Communication Services direct routing configuration, select the checkbox for a corresponding domain name, and then select Remove.

Screenshot of removing a custom domain.

Next steps

Conceptual documentation