Switchport packet-rate – Brocade Communications Systems Brocate Ethernet Access Switch 6910 User Manual
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Brocade 6910 Ethernet Access Switch Configuration Guide
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Interface Commands
12
switchport packet-rate
This command configures broadcast, multicast and unknown unicast storm control. Use the no
form to restore the default setting.
Syntax
switchport {broadcast | multicast | unicast} packet-rate rate
no switchport {broadcast | multicast | unicast}
broadcast - Specifies storm control for broadcast traffic.
multicast - Specifies storm control for multicast traffic.
unicast - Specifies storm control for unknown unicast traffic.
rate - Threshold level as a rate; i.e., kilobits per second.
(Range: 64-100000 Kbps for Fast Ethernet ports,
64-1000000 Kbps for Gigabit Ethernet ports)
Default Setting
Broadcast Storm Control: Enabled, packet-rate limit: 64 kbps
Multicast Storm Control: Disabled
Unknown Unicast Storm Control: Disabled
Command Mode
Interface Configuration (Ethernet)
Command Usage
•
When traffic exceeds the threshold specified for broadcast and multicast or unknown unicast
traffic, packets exceeding the threshold are dropped until the rate falls back down beneath the
threshold.
•
Traffic storms can be controlled at the hardware level using this command or at the software
level using the
command. However, only one of these control types can be
applied to a port. Enabling hardware-level storm control on a port will disable automatic storm
control on that port.
•
The rate limits set by this command are also used by automatic storm control when the control
response is set to rate limiting by the
command.
•
Using both rate limiting and storm control on the same interface may lead to unexpected
results. For example, suppose broadcast storm control is set to 500 Kbps by the command
“switchport broadcast packet-rate 500,” and the rate limit is set to 20000 Kbps by the
command “rate-limit input 20000" on a Fast Ethernet port. Since 20000 Kbps is 1/5 of line
speed (100 Mbps), the received rate will actually be 100 Kbps, or 1/5 of the 500 Kbps limit set
by the storm control command. It is therefore not advisable to use both of these commands on
the same interface.
Example
The following shows how to configure broadcast storm control at 600 kilobits per second:
Console(config)#interface ethernet 1/5
Console(config-if)#switchport broadcast packet-rate 600
Console(config-if)#