github.com/openshift/installer@v1.4.17/docs/user/azure/dnszone.md (about)

     1  # Public DNS Zone
     2  
     3  Azure's DNS Zone service is used by the OpenShift installer to configure cluster DNS resolution and provide name lookup
     4  for the cluster to the outside world. To use OpenShift, you must have created a public DNS zone in Azure in
     5  the same subscription as your OpenShift cluster. You must also ensure the zone is "authoritative" for the domain. There are
     6  two ways to do this outlined below: root domain and subdomain. A root domain is `example.com`. A subdomain is of
     7  the form `clusters.example.com`.
     8  
     9  The below sections identify how to ensure your hosted zone is authoritative for a domain.
    10  
    11  ## Step 1: Acquire/Identify Domain
    12  
    13  You may skip this step if using an existing domain and registrar. You will move the authoritative DNS to Azure or
    14  submit a delegation request for a subdomain in a later step.
    15  
    16  Azure can also purchase domains for you and act as a registrar. If you allow Azure to purchase a new domain for you,
    17  you can skip the remainder of these steps (the domain is created and the hosted zone is created correctly for you)!
    18  
    19  [Documentation][buy-domain-from-azure] on buying domain for Azure
    20  
    21  ## Step 2: Create Public Hosted Zone
    22  
    23  Whether using a root domain or a subdomain, you must create a public, hosted zone.
    24  
    25  [Azure: Creating a Public DNS Zone][create-hosted-zone]
    26  
    27  To use the root domain, you'd create the hosted zone with the value `example.com`. To use a subdomain, you'd
    28  create a hosted zone with the value `clusters.example.com`. (Use appropriate domain values for your situation.)
    29  
    30  [buy-domain-from-azure]: https://docs.microsoft.com/en-us/azure/app-service/manage-custom-dns-buy-domain
    31  [create-hosted-zone]: https://docs.microsoft.com/en-us/azure/dns/dns-delegate-domain-azure-dns