User`s guide

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Configuration – Network > DNS Servers
This section describes the parameters used to configure the DNS server functionality of the
router.
Configuration – Network > DNS Servers > DNS Server n
The DNS server selection parameters give the ability to specify a DNS server based on the
DNS query. For example, DNS lookups for internal servers can be directed to an internal
DNS server and all other DNS requests can be sent direct to an external DNS server
managed by the ISP.
For DNS requests matching pattern, send the request to
This text box contains the hostname pattern to match for the specified DNS server. This
parameter needs a wildcard to prefix the domain name. For example, to match DNS queries
for all digi.com servers, enter *.digi.com.
When using this feature, it is recommended that the last DNS server selection hostname
pattern is set to “*” to match all other DNS lookups. This ensures that all the DNS lookup
configuration is kept together for ease of troubleshooting. If this is not done, the lookups
will use the DNS server configured on the interface of the default route.
DNS Server a.b.c.d
The value in this text box specifies the IP address of the DNS server to use when a DNS
request matches the hostname pattern.
Secondary DNS Server a.b.c.d
In the event of the primary DNS server not being available, the IP address in this text box
specifies the destination for DNS queries matching the hostname pattern.
Route using
Routing table / Interface x,y
The two radio buttons associated with this text control whether the router should look up
the route to the DNS server by using the routing table or should send the DNS query out of
a specific interface. When the Interface radio button is selected, the drop-down box and
interface instance text box are enabled. The options available for the interface are PPP and
Ethernet. The adjacent text box should be filled in with the number of a valid instance of the
interface, e.g. Ethernet 3. (Different models of router support different numbers of
interfaces).
Use source IP Address of
Sending interface / Interface x,y
The two radio buttons control whether the DNS query should go out having the source
address of the sending interface or a different interface. This will be required for routing if
the route to the DNS server is via an IPsec tunnel, to ensure the local and remote subnet
selectors match.