Dell S4048T User Manual

Resolution of Host Names
Domain name service (DNS) maps host names to IP addresses. This feature simplifies commands such 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.
In a dual stack setup, the system sends both A ( for IPv4 — RFC 1035) and AAAA ( for IPv6 — RFC 3596) record
requests to a DNS server even if you configure only the ip name-server 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
Name server, Domain name, and Domain list are VRF specific. The maximum number of Name servers and
Domain lists per VRF is six.
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.
Example of the show hosts Command
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
IPv4 Routing 504

Dell S4048T Specifications

General

Switching Capacity	1.44 Tbps
Rack Units	1U
Form Factor	Rack-mountable
Power Device	Internal power supply
Power Redundancy	Optional
Product Type	Switch
Jumbo Frame Support	Yes
Routing Protocol	OSPF, BGP, RIP, VRRP, PIM-SM, IGMP
Remote Management Protocol	SNMP, RMON, Telnet, SSH
Features	Quality of Service (QoS), Jumbo Frames Support, Virtual Route Redundancy Protocol (VRRP), VLAN support, sFlow, Multiple Spanning Tree Protocol (MSTP), Rapid Spanning Tree Protocol (RSTP), IPv6 support
Compliant Standards	IEEE 802.3, IEEE 802.3u, IEEE 802.3ab, IEEE 802.3ae
Dimensions (W x D x H)	17.3 in x 16 in x 1.7 in
Operating Temperature	0°C to 40 °C
Operating Humidity	10% to 90% (non-condensing)