Enabling Directed Broadcast; Resolution Of Host Names; Enabling Dynamic Resolution Of Host Names - Dell Z9000 Configuration Manual

To configure the duration for which the device waits for the ACK packet to be sent from the requesting
host to establish the TCP connection, perform the following steps:
1. Define the wait duration in seconds for the TCP connection to be established.
CONFIGURATION mode
Dell(conf)#ip tcp reduced-syn-ack-wait <9-75>
You can use the no ip tcp reduced-syn-ack-wait command to restore the default behavior,
which causes the wait period to be set as 8 seconds.
2. View the interval that you configured for the device to wait before the TCP connection is attempted
to be established.
EXEC mode
Dell>show ip tcp reduced-syn-ack-wait

Enabling Directed Broadcast

By default, Dell Networking OS drops directed broadcast packets destined for an interface. This default
setting provides some protection against denial of service (DoS) attacks.
To enable Dell Networking OS 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
IPv4 Routing
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