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Table Of Contents
Enabling Directed Broadcast
By default, the system drops directed broadcast packets destined for an interface. This default setting provides some protection
against denial of service (DoS) attacks.
To enable the system to receive directed broadcasts, use the following command.
Enable directed broadcast.
INTERFACE mode
ip directed-broadcast
To view the configuration, use the show config command in INTERFACE mode.
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.
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IPv4 Routing