Limiting Traffic On Individual Ports; Enabling Flow Control On A Port - 3Com 4200G 12-Port Configuration Manual

Only ports on the front panel of the device support the auto-negotiation speed configuration feature.
And ports on the extended interface card do not support this feature currently.
After you configure auto-negotiation speed(s) for a port, if you execute the undo speed command
or the speed auto command, the auto-negotiation speed setting of the port restores to the default
setting.
The effect of executing speed auto 10 100 1000 equals to that of executing speed auto, that is,
the port is configured to support all the auto-negotiation speeds: 10 Mbps, 100 Mbps, and 1000
Mbps.

Limiting Traffic on individual Ports

By performing the following configurations, you can limit the incoming broadcast traffic on individual
ports. When a type of incoming traffic exceeds the threshold you set, the system drops the packets
exceeding the traffic limit to reduce the traffic ratio of this type to the reasonable range, so as to keep
normal network service.
Follow these steps to limit traffic on port:
To do...
Enter system view
Limit broadcast traffic received
on each port
Enter Ethernet port view
Limit broadcast traffic received
on the current port

Enabling Flow Control on a Port

Flow control is enabled on both the local and peer switches. If congestion occurs on the local switch:
The local switch sends a message to notify the peer switch of stopping sending packets to itself or
reducing the sending rate temporarily.
The peer switch will stop sending packets to the local switch or reduce the sending rate temporarily
when it receives the message; and vice versa. By this way, packet loss is avoided and the network
service operates normally.
Follow these steps to enable flow control on a port:
To do...
Enter system view
Enter Ethernet port view
Use the command...
system-view
broadcast-suppression { ratio
| pps max-pps }
interface interface-type
interface-number
broadcast-suppression { ratio
| pps max-pps }
Use the command...
system-view
interface interface-type
interface-number
1-3
Remarks
—
Optional
By default, the switch does not
suppress broadcast traffic.
—
Optional
By default, the switch does not
suppress broadcast traffic.
Remarks
—
—