Configuring the VAST Cluster DNS Service

  • Updated on Feb 3, 2026
  • Published on Jan 28, 2026
  • 2 minute(s) read
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VAST Cluster supports a single instance of the DNS service. The DNS service listens for DNS requests on port 53 and runs on a dedicated IP.

The service instance supports a single DNS delegation that refers DNS requests with a common domain suffix. The DNS service resolves DNS names to virtual IP pools per short domain names configured per virtual IP pool.  

To use the DNS service:

Configuring the VAST Cluster DNS Service via VAST Web UI

  1. From the left navigation menu, select Network Access and then DNS.

  2. In the DNS page that opens, click Create DNS Service.

  3. In the Add DNS dialog, complete the fields:

    Field

    Description

    DNS Service Name (required)

    Enter a name for the DNS service.

    For example: vast-dns

    DNS Service IP (required)

    Enter an IP address to assign to the DNS service.

    For example: 192.0.2.0

    DNS Service Gateway

    If the external DNS server doesn't reside on the same IP subnet as the DNS VIP, enter the IP address of a gateway through which to connect to the DNS service. The gateway IP address must be on same subnet as the DNS Service IP and reachable from the management network.

    For example: 192.0.4.0

    DNS Service Suffix

    Specify a domain suffix. This is the domain suffix that your external DNS server should be configured to delegate to the DNS Service IP,

    The domain suffix is appended to VIP pool domain names to form a valid FQDN for DNS requests to target.

    Example: mycorp.cluster.com

    DNS Service Subnet CIDR

    The IP subnet, in CIDR format, on which the DNS Service IP  resides.

    In CIDR notation, the subnet is expressed as the number of bits of each IP address that represent the subnet address.

    For example, the subnet mask 255.255.0.0 is expressed as 16 in CIDR notation.

    Enter only the trailing CIDR decimal number that indicates the subnet mask. e.g. If the DNS Service IP is 192.0.2.3 and the CIDR subnet is 24, enter 24 in this field. Do not enter 192.0.2.3/24.

    DNS Service VLAN

    If your external DNS server is only exposed to a specific VLAN, you can enter the VLAN here to enable communication with the DNS server. Ensure that VLAN tagging is configured on the MGMT network to which the CNodes are connected. This configuration is not supported through VMS.

    Note

    This VLAN tag is not related to VLAN tagging per VIP pool.

    Valid range: 1 to 4094

    All CNodes selected

    This option lets you determine which CNodes serve DNS.

    If you want to dedicate a specific group of CNodes to DNS, toggle this option off and in the pane that appears  below it, select CNodes that you want to be included.

    Otherwise, all CNodes are used.

    Port Type

    Specifies which interface listens for DNS service delegation requests:

    • EXTERNAL_PORT (default). The onboard server management interface.

    • NORTH_PORT. The client-facing network interface.

    • SOUTH_PORT. The internal network interface.

    TTL

    Sets the TTL for the interface selected in Port Type.

    DNS Port

    Specifies the DNS port number.

  4. If you want to immediately enable the DNS service, toggle Enabled on.

  5. Click Create.

    The DNS server configuration is created and displayed in the DNS page.

Configuring the VAST Cluster DNS Service via the VAST CLI

To configure the DNS server from the CLI, use the dns create command.

For example:

vcli: admin> dns create --name vast_dns --ip 192.0.2.0 --domain-suffix vastdata.ourcorp.com --gateway 192.0.4.0--enable --subnet-cidr 16

To display the configuration, run dns show or dns list.

To modify the configuration, run dns modify.

To delete the configuration, run dns delete.

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