D-Link DFL-2560 Product Manual - Page 139
DNS, Fully Qualified Domain Name, Uniform Resource Locator, Primary Server, Secondary Server
UPC - 790069335433
View all D-Link DFL-2560 manuals
Add to My Manuals
Save this manual to your list of manuals |
Page 139 highlights
3.9. DNS Chapter 3. Fundamentals 3.9. DNS Overview A DNS server can resolve a Fully Qualified Domain Name (FQDN) into the corresponding numeric IP address. FQDNs are unambiguous textual domain names which specify a node's unique position in the Internet's DNS tree hierarchy. FQDN resolution allows the actual physical IP address to change while the FQDN can stay the same. A Uniform Resource Locator (URL) differs from an FQDN in that the URL includes the access protocol along with the FQDN. For example the protocol might be specified http//: for world wide web pages. FQDNs are used in many aspects of a NetDefendOS configuration where IP addresses are unknown or where it makes more sense to make use of DNS resolution instead of using static IP addresses. DNS with NetDefendOS To accomplish DNS resolution, NetDefendOS has a built-in DNS client that can be configured to make use of up to three DNS servers. The are called the Primary Server, the Secondary Server and the Tertiary Server. For DNS to function, at least the primary server must be configured. It is recommended to have both a primary and secondary defined so that there is a backup should the primary be unavailable. Features Requiring DNS Resolution Having at least one DNS server defined is vital for functioning of the following modules in NetDefendOS: • Automatic time synchronization. • Access to an external certificate authority server for CA signed certificates. • UTM features that require access to external servers such as anti-virus and IDP. Example 3.28. Configuring DNS Servers In this example, the DNS client is configured to use one primary and one secondary DNS server, having IP addresses 10.0.0.1 and 10.0.0.2 respectively. Command-Line Interface gw-world:/> set DNS DNSServer1=10.0.0.1 DNSServer2=10.0.0.2 Web Interface 1. Go to System > DNS 2. Enter the following: • Primary Server: 10.0.0.1 • Secondary Server: 10.0.0.2 3. Click OK 139