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device to slow down the sending speed to prevent packet loss when traffic received
exceeds the capacity of port cache. ES4704BD’s ports support IEEE802.3X flow control;
the ports work in half-duplex mode, supporting back-pressure flow control. If flow control
results in serious HOL, the switch will automatically start HOL control (discarding some
packets in the COS queue that may result in HOL) to prevent drastic degradation of
network performance.
Note:
Port flow control function is NOT recommended unless the users need a
slow speed, low performance network with low packet loss.
Flow control will not
work between different cards in the switch. When enable the port flow control function,
speed and duplex mode of both ends should be the same.
Example:
Enable the flow control function in ports 1/1-8.
Switch(Config)#interface ethernet 1/1-8
Switch(Config-Port-Range)#flow control
4.2.1.2.5 interface Ethernet
Command: interface ethernet <interface-list>
Function:
Enters Ethernet Interface Mode from Global Mode.
Parameters: <interface-list>
stands for port number.
Command mode:
Global Mode
Usage Guide:
Run the
exit
command to exit the Ethernet Interface Mode to Global
Mode.
Example:
Entering the Ethernet Interface Mode for ports 1/1, 2/4-5, 3/8.
Switch(Config)#interface ethernet 1/1;2/4-5;3/8
4.2.1.2.6 loopback
Command:loopback
no loopback
Function:
Enables the loopback test function in an Ethernet port; the “
no loopback
”
command disables the loopback test on an Ethernet port.
Command mode:
Interface Mode
Default:
Loopback test is disabled in Ethernet port by default.
Usage Guide:
Loopback test can be used to verify the Ethernet ports are working
normally. After loopback has been enabled, the port will assume a connection established
to itself, and all traffic sent from the port will be received at the very same port.
Example:
Enable loopback test in Ethernet ports 1/1 -8
Switch(Config)#interface ethernet 1/1-8
Switch(Config-Port-Range)#loopback
4.2.1.2.7 mdi
Command: mdi { auto | across | normal }