Connecting transceivers to fixed-configuration devices

Cause
If the switch either fails to show a link between an installed transceiver and another device or demonstrates errors or other unexpected behavior on the link, check the port configuration on both devices for a speed and/or duplex (mode) mismatch.

  • To check the mode setting for a port on the switch, use either the Port Status screen in the menu interface or show interfaces brief in the CLI.

  • To display information about the transceivers installed on a switch, enter the show tech receivers command in the CLI.

Enabled

Yes (default): The port is ready for a network connection.

No: The port will not operate, even if properly connected in a network. Use this setting, for example, if the port needs to be shut down for diagnostic purposes or while you are making topology changes.

Status (read-only

Up: The port senses a link beat.

Mode

The port's speed and duplex (data transfer operation) setting.

10/100/1000Base-T Ports:

  • Auto-MDIX (default): Senses speed and negotiates with the port at the other end of the link for port operation (MDI-X or MDI.)

    To see what the switch negotiates for the auto setting, use the CLI show interfaces brief command or the 3. Port Status option under 1. Status and Counters in the menu interface.

  • MDI: Sets the port to connect with a PC using a crossover cable (manual mode—applies only to copper port switches using twisted-pair copper Ethernet cables)
  • MDIX: Sets the port to connect with a PC using a straight-through cable (manual mode—applies only to copper port switches using twisted-pair copper Ethernet cables)
  • Auto-10: Allows the port to negotiate between half-duplex (HDx) and full-duplex (FDx) while keeping speed at 10 Mbps. Also negotiates flow control (enabled or disabled.) Hewlett Packard Enterprise recommends auto-10 for links between 10/100 auto-sensing ports connected with Cat 3 cabling. (Cat 5 cabling is required for 100 Mbps links.)
  • 10HDx:10 Mbps, half-duplex
  • 10FDx: 10 Mbps, full-duplex
  • Auto-100: Uses 100 Mbps and negotiates with the port at the other end of the link for other port operation features.
  • Auto-10-100: Allows the port to establish a link with the port at the other end at either 10 Mbps or 100 Mbps, using the highest mutual speed and duplex mode available. Only these speeds are allowed with this setting.
  • Auto-1000: Uses 1000 Mbps and negotiates with the port at the other end of the link for other port operation features.
  • 100Hdx: Uses 100 Mbps, half-duplex.
  • 100Fdx: Uses 100 Mbps, full-duplex
Gigabit Fiber-Optic Ports (Gigabit-SX, Gigabit-LX, and Gigabit-LH):
  • 1000FDx: 1000 Mbps (1 Gbps), full-duplex only
  • Auto (default): The port operates at 1000FDx and auto-negotiates flow control with the device connected to the port.
Gigabit Copper Ports:
  • 1000FDx: 1000 Mbps (1 Gbps), full-duplex only
  • Auto (default): The port operates at 1000FDx and auto-negotiates flow control with the device connected to the port.
10-Gigabit CX4 Copper Ports:

  • Auto: The port operates at 10 gigabits FDx and negotiates flow control. Lower speed settings or half-duplex are not allowed.

10-Gigabit SC Fiber-Optic Ports (10-GbE SR, 10-GbE LR, 10-GbE ER):

  • Auto: The port operates at 10 gigabits FDx and negotiates flow control. Lower speed settings or half-duplex are not allowed.

NOTE:

Conditioning patch cord cables are not supported on 10-GbE.

Auto-MDIX

The switch supports Auto-MDIX on 10Mb, 100Mb, and 1 Gb T/TX (copper) ports. (Fiber ports and 10-gigabit ports do not use this feature.)

  • Automdix: Configures the port for automatic detection of the cable type (straight-through or crossover.)
  • MDI: Configures the port to connect to a switch, hub, or other MDI-X device with a straight-through cable.
  • MDIX: Configures the port to connect to a PC or other MDI device with a straight-through cable.
flow-control
  • Disabled (default): The port does not generate flow control packets, and drops any flow control packets it receives.
  • Enabled: The port uses 802.3x link layer flow control, generates flow-control packets, and processes received flow-control packets.

With the port mode set to Auto (the default) and flow control enabled, the switch negotiates flow control on the indicated port. If the port mode is not set to Auto, or if flow control is disabled on the port, flow control is not used. Note that flow control must be enabled on both ends of a link.

Broadcast limit

Specifies the percentage of the theoretical maximum network bandwidth that can be used for broadcast traffic. Any broadcast traffic exceeding that limit will be dropped. Zero (0) means the feature is disabled.

The broadcast-limit command operates at the port context level to set the broadcast limit for a port on the switch.

NOTE:

This feature is not appropriate for networks that require high levels of IPX or RIP broadcast traffic.