You can configure flow control for Gigabit Ethernet interfaces and for 100Base-T/1000Base-T and 10Base-T/100Base-T/1000Base-T interfaces.
The flowcontrol option of the ifconfig command sets the flow control of the abovementioned interfaces. This configured flow control setting is advertised during autonegotiation. If autonegotiation succeeds, the operational flow control setting is determined based on the negotiated speed and the value advertised by the other device. If autonegotiation fails, the configured flow control setting is used.
Flow control manages the flow of frames between two directly connected link partners. This is done by using packets called Pause frames. For example, a link partner A sends a Pause On frame to link partner B when its receive buffers are nearly full. The link partner B suspends transmission until it receives a Pause Off frame from the link partner A or a specified timeout threshold is reached. Thus, flow control can reduce or eliminate dropped packets due to overrun.
The following table describes the types you can specify for the flowcontrol option.
You can use the ifconfig command to configure and display the configured flow control setting and the ifstat command to view the operational flow control setting. If you do not specify the flowcontrol option with the ifconfig command, then the configured flow control setting defaults to full.
To configure the flow control of an interface, complete the following step.
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File: ifconfi8.htm
Last updated: 01/20/03 14:16:40