8 | Release Note |
If the DNS servers have already been configured, the configuration information can be set using the command:
SET IP DNS
For example, to add or set the IP addresses of the default primary and secondary name servers to 192.168.20.1 and 192.168.20.2 respectively, use the commands:
ADD IP DNS PRIMARY=192.168.20.1 SECONDARY=192.168.20.2
SET IP DNS PRIMARY=192.168.20.1 SECONDARY=192.168.20.2
To set the DNS cache size and timeout values, use the command:
SET IP DNS CACHE
The name server information can be deleted from the DNS server by using the command:
DELETE IP DNS
Server Selection
The router can be configured to use a range of DNS servers with different servers being selected based on the host name being resolved.
The DOMAIN parameter in the ADD IP DNS command allows the user to specify a suffix that must be present on a host name in order for the name servers specified by the command to be used.
If the DOMAIN parameter is not specified, the name servers will be used as the default name servers. All DNS requests that do not match another specified domain will be sent to the default name servers. This is equivalent to specifying DOMAIN=ANY.
To add primary and secondary name servers with IP addresses of 202.36.163.1 and 202.36.163.3 respectively, for use as default name servers, use the command:
ADD IP DNS DOMAIN=ANY PRIMARY=202.36.163.1
SECONDARY=202.36.1.3
These servers will be used for all host names that do not match any of the domains that are configured with their own set of name servers.
For example, to add primary and secondary name servers with IP addresses of 192.168.10.1 and 192.168.10.2 respectively, for use when resolving host names in the domain apples.com, use the command:
ADD IP DNS DOMAIN=apples.com PRIMARY=192.168.1.1
SECONDARY=192.168.1.2
If a request is sent for the domain www.fruit.apples.com, the DNS servers at 192.168.1.1 or 192.168.1.2 will be used, as the domain matches apples.com.
If a request is sent for the domain ftp.fruitpunch.apples.com, the DNS servers at 192.168.1.1 or 192.168.1.2 will also be used, as the domain matches apples.com.
If a request is sent for the domain www.armadillo.com, the domain does not match apples.com, so the ANY servers 202.36.1.1 or 202.36.1.3 will be used.
Software Release 2.3.1
