Reference Guide
Resolution of Host Names
Domain name service (DNS) maps host names to IP addresses. This feature simplifies such commands as Telnet and FTP by
allowing you to enter a name instead of an IP address.
Dynamic resolution of host names is disabled by default. Unless you enable the feature, the system resolves only host names
entered into the host table with the ip host command.
The following sections describe DNS and the resolution of host names.
● Enabling Dynamic Resolution of Host Names
● Specifying the Local System Domain and a List of Domains
● Configuring DNS with Traceroute
Enabling Dynamic Resolution of Host Names
By default, dynamic resolution of host names (DNS) is disabled.
To enable DNS, use the following commands.
● Enable dynamic resolution of host names.
CONFIGURATION mode
ip domain-lookup
● Specify up to six name servers.
CONFIGURATION mode
ip name-server ip-address [ip-address2 ... ip-address6]
The order you entered the servers determines the order of their use.
To view current bindings, use the show hosts command.
Dell>show host
Default domain is force10networks.com
Name/address lookup uses domain service
Name servers are not set
Host Flags TTL Type Address
-------- ----- ---- ---- -------
ks (perm, OK) - IP 2.2.2.2
patch1 (perm, OK) - IP 192.68.69.2
tomm-3 (perm, OK) - IP 192.68.99.2
gxr (perm, OK) - IP 192.71.18.2
f00-3 (perm, OK) - IP 192.71.23.1
Dell>
To view the current configuration, use the show running-config resolve command.
Specifying the Local System Domain and a List of
Domains
If you enter a partial domain, the system can search different domains to finish or fully qualify that partial domain.
A fully qualified domain name (FQDN) is any name that is terminated with a period/dot. The system searches the host table first
to resolve the partial domain. The host table contains both statically configured and dynamically learnt host and IP addresses. If
the system cannot resolve the domain, it tries the domain name assigned to the local system. If that does not resolve the partial
domain, the system searches the list of domains configured.
To configure a domain name or a list of domain names, use the following commands.
● Enter up to 63 characters to configure one domain name.
CONFIGURATION mode
ip domain-name name
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IPv4 Routing