User`s guide

Synology DiskStation User's Guide
Based on DSM 4.2
89 Chapter 18: Create a Domain Name Server with DNS Server
 Check firewall or port forwarding settings: DNS services require the use of TCP and UDP port 53. If your
DiskStation uses a firewall, this port must be opened. If the DiskStation connects to the Internet through a
router, set up port forwarding rules and open TCP and UDP port 53.
 Register your device: After you set up DNS Server, remember to register the IP address and other required
information of your DiskStation with the provider of your domain name. Otherwise, clients will be unable to
query your DiskStation over the Internet. Consult your domain name provider for more information.
DNS Server Features
Once properly installed and setup, DNS Server provides the below features. For more detailed instructions
regarding these and other features, please see DSM Help.
Zones
This page provides options to manage your domain names by creating and modifying zones. A zone refers to a
portion of the domain name space for which a domain name server is authoritative and possesses complete
information. With DNS Server, zone files can be created, stored, and managed on the DiskStation.
Zones are divided into two types: master zones and slave zones. Master zones possess information for zone files.
Slave zones synchronize zone files from master zones (an operation called zone transfer).
Resolution
You can enable resolution services to allow the DiskStation to resolve recursive queries. A recursive query
occurs when the DiskStation is not authoritative for a requested domain. In this case, the DiskStation queries
other domain name servers until the information is found, or until the query fails.
For example, if a client queries your DiskStation for the address of "synology.com," but your DiskStation is not
authoritative for this domain (i.e. you do not own synology.com), it will query other domain name servers or
forward the request to specified forwarder servers, and then relay the result back to the sender of the query.
Keys
TSIG (Transfer Signature) keys limit what hosts are allowed to synchronize zone files from the master server.
This page displays the keys currently used by DNS Server.
Views
A domain name server can present different information to different clients by implementing views. This function,
sometimes called spilt-horizon DNS, can improve security and privacy management of DNS zone records. For
example, you have one domain name, but wish to provide different responses to queries from external and
internal sources. In such cases, you can create different views with separate resource records.