Installation guide

Configuring the Switch
3-146
3
Setting Broadcast Storm Thresholds
Broadcast storms may occur when a device on your network is malfunctioning, or if
application programs are not well designed or properly configured. If there is too
much broadcast traffic on your network, performance can be severely degraded or
everything can come to complete halt.
You can protect your network from broadcast storms by setting a threshold for
broadcast traffic for each port. Any broadcast packets exceeding the specified
threshold will then be dropped.
Command Usage
• Broadcast Storm Control is enabled by default.
• Broadcast control does not effect IP multicast traffic.
• Due to an ASIC chip limitation, the supported storm control modes include:
- broadcast
- broadcast + multicast
- broadcast + multicast + unknown unicast
This means that when mulicast storm control is enabled, broadcast storm control
is also enabled (using the threshold value set by the multicast storm control
command). And when unknown unicast storm control is enabled, both multicast
and unknown unicast storm control are also enabled (using the threshold value set
by the unknown unicast storm control command).
Note: Multicast and unknown unicast storm thresholds can only be set using the CLI
(see the “switchport packet-rate” command on page 4-189).
Command Attributes
• Port
8
- Port number. (Range: 1-28)
•Type – Indicates the port type. (100BASE-TX, 1000BASE-T, or 1000BASE-SFP)
• Protect Status – Enables or disables broadcast storm control. (Default: Enabled)
• Threshold – Threshold level as a rate; i.e., kilobits per second.
(Range: 64-100000 kilobits per second for Fast Ethernet ports; 64-1000000 kilobits
per second for Gigabit ports; Default: 64 kilobits per second)
• Trunk
9
– Shows if a port is a trunk member.
8. Port Broadcast Control
9. Trunk Broadcast Control