DLS will provide a variety of DNS services for DLS Internet Dedicated Internet and Intranet customers. DLS's Domain Name System (DNS) Policy is designed to support consistent and reliable Domain Name service for the majority of its customers. DLS utilizes the Berkeley Internet Name Domain (BIND) software for name resolution service.

DLS Internet DNS (Dedicated Internet) DLS Internet provides Primary DNS for a fee for second-level domains (i.e. customer.com) and Secondary DNS. DLS Internet employs DLS Domain Manager which allows customers to add, delete, and modify domain names hosted on DLS DNS servers. The DLS Internet name servers are detecting changes implemented via DNS manager every 5 and reload DNS zones. Changes made will not appear until these reloads complete. As a courtesy, DLS Internet will respond to requests for Zone changes received through technical support. Any such request for assistance should be sent as a Technical Support Ticket. These requests will be handled in a first come, first serve basis and generally be treated as low priority support requests.

Primary DNS Note that it is the Customer's responsibility to register their domain, with an appropriate registrar  and to supply the registrar with names and IP addresses of the DLS Internet Name Servers. If customer opts to enlist assistance from DLS to implement zone changes - DLS requires a minimum of 36 hours notice for any new DNS requests or changes to existing DNS records.

The customer is responsible for providing DLS with all appropriate information to set up the domain, including host names, IP addresses for those hosts, as well as indicating the mail exchanger host name and address. The customer is responsible for determining if reverse resolution is needed. DLS will not provide reverse resolution by default - please, open technical support ticket. Please use the DLS Domain Manager to set up or change your DLS DNS.

Before calling or writing DLS for assistance with Primary DNS services, please verify that you have registered your domain properly, and have also registered the DLS Internet name servers with your registrar as being Primary for your domain.

Secondary DNS Requirements Please note that in the case where DLS provides Secondary DNS, the customer is responsible for maintaining the domain(s) in question. DLS servers will only mirror the customer configured information, and can only do so if the customer name servers are reachable and functioning. The performance of DLS's Secondary DNS service is entirely dependent upon the performance and availability of the customer's Primary name servers.

If DLS is providing Primary and Secondary DNS, all conditions for proper installation of Secondary will automatically be met upon receiving the appropriate host name and IP address information, as well as information identifying the mail exchangers.

When providing Secondary DNS services only:

1. DLS will provide Secondary Resolution (DNS Authoritative Slave).
2. DLS will provide Secondary DNS for any zone that is answering Authoritatively, provided the customer has opened a support ticket in advance of the need of these services. Note that this also requires an SOA record as well as name server records in the zone file on the customer maintained Primary Name server.
3. Please double check the Primary name server's zone file and verify that it contains a Start Of Authority (SOA) record identifying the domain, Primary name server, and the DNS administrator's address.
4. Please note that TCP and UDP connection requests on port 53 must be permitted to the Primary name servers resolving the domain.
5. Please verify that the DLS Internet name servers are permitted to access your Primary name server on TCP and UDP port 53. This is necessary so that the DLS name servers may perform zone file transfers.
6. Please verify that the Zone file on the Primary name server contains name server (NS) records pointing to the Authoritative DLS Internet name servers.
7. As DNS resolution services are a shared resource, DLS automatically configures SOA record to match the settings below to minimize load and maximize resolution performance for all customers:

Suggested Value/Format	SOA Field
YYYYMMDDnn	Serial Number (Four digit year, two digit month, two digit day and version number of the file)
43200	Refresh
3600	Retry
2419200	Expire
86400	TTL (Time to Live)

8. Before calling DLS, please verify that you have registered your domain properly, and also registered the DLS Internet name servers with your registrar as being secondary for your domain.

Reverse DNS Requirements When a customer requests to do reverse DNS, the customer must meet the following requirements before DLS will agree to provide the service.

1. Customer has obtained IP address space/block from DLS
2. Customer has decided which of these they want to do.
   • DLS to be the Primary, the customer must provide teh following to DLS:
     1. IP address the customer wants reverse DNS with the corresponding fully qualified hostnames that they resolve too.
   • If customer wants to do their own Primary, DLS can only forward or delegate the responsibilities of reverse DNS zone to the customer. The customer must provide the following to DLS:
     1. All IP addresses to be delegated from DLS
     2. IP addresses and fully qualified hostnames of their nameservers.

Additional Information DLS does not provide Primary DNS service to customers who are considered to be Internet Resellers (such as an ISP, Virtual Hosting Service, etc).

DLS can provide Secondary DNS to customers who are considered to be Internet Resellers, but only for the second-level comain of the customer (not the customer's customers).

All DNS configuration requests must supply either:

1. Customer Account number.
2. Network Address number (IP).

This information is necessary to access your account and process your request. Any request missing this information will be returned to the sender. Requests to set up or modify DLS managed DNS services must be completed through the Technial Support Ticket. This web form address is maintained currently by the DLS Internet Support Team. All e-mail configuration requests will be responded to within 36 hours of receipt by the DLS Internet Support Team.

DLS will not verify information supplied for Primary zones. It is the customer's responsibility to insure that the information submitted is correct and accurate. As of the date of publication of this document, DLS uses BIND v8.2.3 and BIND v9.2.