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You can display and change information about the ports on the current Switch unit in the stack using the commands on the Ethernet menu. These commands allow you to:
To display and change information about the ports on another Switch unit in the stack, you need to select that unit using the unit command For more information, see "Moving the Focus of the Command Line Interface".
You can enable and disable Ethernet ports on the Switch using the portState command on the Ethernet menu.
By default, all ports on the Switch are enabled.
To enable or disable a port:
1 . At the Top-level menu, enter:
ethernet portState
Select Ethernet port(s) (1-24):
2 . Enter the number of the port to be enabled or disabled.
Enter new value (enable, disable) [enable]:
3 . Enter enable or disable.
You can specify the speed and duplex mode of Ethernet ports on the Switch using the portMode command on the Ethernet menu.
To specify the speed and duplex mode of a port:
1 . At the Top-level menu, enter:
ethernet portMode
Select Ethernet port (1-24,all):
2 . Enter the number of the port to have its speed and duplex mode specified, or enter all for all the ports.
Enter new value (10half,10full,100half,100full):
Enter new value (100half,100full):
Enter new value (10half,10full):
3 . Enter the new speed and duplex mode.
CAUTION: To communicate without errors, both ends of a link must use the same duplex mode.
Port speeds and duplex modes specified using the portMode command do not take effect until auto-negotiation is disabled on the port. For more information, see "Enabling and Disabling Auto-negotiation"
Auto-negotiation is a system that allows Switch units to automatically detect the speed and duplex mode of twisted pair links, and set the speed and duplex mode of its twisted pair ports accordingly:
CAUTION: The duplex mode of a link is not detected if the port on the other end of the link is not auto-negotiating. In this case, the Switch port is set to operate in half duplex:
If you want the link to operate in full duplex, set the Switch port to operate in full duplex manually. For more information, see "Specifying the Speed and Duplex Mode".
You can enable and disable auto-negotiation for Ethernet ports on the Switch using the autoNegotiation command on the Ethernet menu.
To enable or disable auto-negotiation for a port:
1 . At the Top-level menu, enter:
ethernet autoNegotiation
Select Ethernet port (1-24,all):
2 . Enter the number of the port to have auto-negotiation enabled or disabled, or enter all for all ports.
Enter new value (enable,disable) [enable]:
3 . Enter enable or disable.
Fiber ports and Transceiver Module ports are not auto-negotiating. If the port is one of these ports, auto-negotiation cannot be enabled.
If auto-negotiation is disabled, the speed and duplex mode of the port is set using the portMode command. For more information, see "Specifying the Speed and Duplex Mode".
IEEE 802.3x flow control prevents any packet loss that may occur on congested ports that are operating in full duplex.
You can enable or disable IEEE 802.3x flow control for Ethernet ports on the Switch using the flowControl command on the Ethernet menu.
To enable or disable IEEE 802.3x flow control for a port:
1 . At the Top-level menu, enter:
ethernet flowControl
Select Ethernet port (1-24,all):
2 . Enter the number of the port to have IEEE 802.3x flow control enabled or disabled, or enter all for all the ports.
Enter new value (on,off) [off]:
3 . Enter on or off.
For IEEE 802.3x flow control to operate correctly, it must be enabled at both ends of the link.
You can display statistical information for a port using the statistics command on the Ethernet menu.
To display the statistical information:
1 . At the Top-level menu, enter:
ethernet statistics
Select Ethernet port (1-24):
2 . Enter the number of a port.
Figure 29 Ethernet Statistics
The following statistical information is displayed:
Received Stats
Transmitted Stats
Errors
CRC and alignment errors may be caused by faults in transmitting devices. Change the Network Interface Card (NIC) of the device connected to the port. If this does not solve the problem, check your cables and connections for damage.
Displays the number of packets seen by the port that had a length which was in one of six ranges between 64 and 1518 octets. This information may help you to analyze the efficiency of your network layer protocol.
You can display summary information about Ethernet ports on the Switch using the summary command on the Ethernet menu.
To display the port summary information:
1 . At the Top-level menu, enter:
ethernet summary
Select Ethernet port (1-24,all):
2 . Enter the number of a port, or enter all for all the ports.
An example of the port summary information is shown below:
The statistics that are displayed are gathered in the time interval since the last reset, initialization or power-off/on cycle.