Configuring a Fast Ethernet Fiber Optic Interface and Displaying Status Information

Use the Fast Ethernet Status and Configuration window to display the status of the Fast Ethernet copper interface and its associated Medium Access Unit (MAU). You can also use this window to configure the Fast Ethernet interface before configuring the bridge port associated with the interface.

Note: The Fast Ethernet interfaces on the VNswitch module are automatically configured  when the module is installed.  However, you may need to alter the default settings to maximize network performance, or to accommodate requirements unique to your network environment.

Enabling a Fast Ethernet Interface

Fast Ethernet interfaces on the VNswitch module are automatically enabled when the module is installed.  If you have previously disabled an interface, and need to enable it, perform the following procedure.    

Procedure:

Step Action
1 Select Enabled from the drop-down box next to the Interface field in the Configuration section.
2 Click Apply.

Note:  You do not need to restart the module for the new setting to take effect. The setting is effective immediately.

Disabling a Fast Ethernet Interface

By default, all Fast Ethernet interfaces on the module are enabled. You might need to disable an interface, for example, if you want to logically disconnect a portion of your network while making changes to the network segment's physical environment. 

Procedure:

Step Action
1 Select Disabled from the drop-down box next to the Interface field in the Configuration section.
2 Click Apply.

Note: You do not need to restart the module for the new setting to take effect. The setting is effective immediately.

Configuring Duplex Mode

The duplex mode is set automatically when the VNswitch module is installed and the Fast Ethernet port is connected to the network. Automatic setting of the duplex mode is a function of the auto-negotiation feature, which is enabled by default. If you do not want to establish the duplex mode automatically through auto-negotiation, you can set the duplex mode manually.

Typically, an interface is set for full-duplex mode if it is established as a point-to-point connection to a single device, and for half-duplex if connected to a shared medium supporting multiple devices.

Procedure:

Step Action
1 Select Half or Full duplex from the drop-down box next to the Default Duplex Mode field in the Configuration section.
2 Click Apply.

Field Descriptions

Status
Physical Address MAC address of the interface.
PROM Address Permanent unique Ethernet address in the programmable read-only memory (PROM) for this Fast Ethernet interface.
Network Speed Maximum line speed supported by the interface.
Duplex Mode Currently selected duplex mode:   half-duplex or full-duplex.
MAU Status
Type Current operational type and mode of the Medium Access Unit (MAU).  Possible values are:
  • 10Base-T full-duplex mode
  • 10Base-T half-duplex mode
  • 100Base-T full-duplex mode
  • 100Base-T half-duplex mode
State Current operational state of the MAU associated with the interface.  Possible states are:
  • Operational
  • Not present
  • Unknown
  • Other
Media Avail. State Status of the MAU's connection to the physical medium.  Possible states are:
  • Available
  • Not available
  • Remote fault
  • Unknown
  • Other
Media Avail. State Exits Number of times the MAU has been in the media available state and then changed to another state.
Connector Type of physical connector used by the MAU. Possible connector types are RJ45 MMJs and fiber SC.
Jabber State State to which the MAU transitions if it transmits for an excessive period of time (26 milliseconds). While in jabber state, the MAU disables any further transmission onto the medium until the interface stops transmitting to the MAU for approximately 750 milliseconds. (Applicable to 10Base-T mode only.)

Possible states are:

  • Jabbering
  • Not jabbering
Jabber State Enters Number of times the MAU detected a jabber condition.
False Carrier The number of carrier sense is asserted without a J/K symbol detection.
Error Statistics: Input
Oversized Frames Number of times the interface received a frame that was larger than the maximum size of an Ethernet frame (1518 bytes).
Alignment Error Number of alignment errors received on the interface.
Runts Number of runt packets (frames shorter than 64 bytes) received by the interface since the last restart.
Internal H/W Errors Number of internal hardware errors related to packet reception that do not fall into any other category of counters listed in this window.
FCS Error Number of FCS errors received on the interface.
FIFO Overrun Number of times the Fast Ethernet chipset is unable to store bytes in the local packet buffer as fast as they come off the wire.
Missed Packets Number of times the interface attempted to receive a packet, but the local packet buffer was full.  This error indicates that the network has more traffic than the interface can handle.
Error Statistics: Output
Deferred Transmission Number of times the carrier sense mechanism detects line activity causing  the interface to defer transmission.
Multiple Collisions Number of packets involved in multiple collisions before they are successfully transmitted.
Excess Collisions Number of packets for which transmission fails due to 16 successive collisions on the interface.  This error indicates a high volume of network traffic or hardware problems with the network.
Carrier Sense Errors Number of times the carrier sense condition was lost or never asserted when attempting to transmit a packet on the interface. This error indicates a problem between the interface and its Fast Ethernet transceiver.
Late Collisions Number of times that a collision is detected later than 512 bit times into the transmission of a packet.  This error indicates that the interface failed to defer, or that the network is not configured properly.
Single Collisions Number of packets that have experienced exactly one collision and are then successfully transmitted.
Total Collisions Sum of single collisions plus multiple collisions.
FIFO Underrun Number of times a packet transmission fails due to the inability of the interface to retrieve packets from the local packet buffer fast enough to transmit them onto the network.
SQE Test Error Number of times the interface sends a packet but detects that the transceiver has no heartbeat.  The packet is treated as successfully transmitted because some transceivers do not generate heartbeats.
Internal H/W Errors Number of internal hardware errors related to packet transmission that do not fall into any other category of counters listed in this window. 

Fast Ethernet Interface Configuration

Interface Specifies whether the interface is enabled or disabled.
Default Duplex Mode Specifies the current duplex mode configured on the interface.