External Port Default Settings; Auto-Negotiation - Dell PowerConnect 5316M User Manual

(MDI/MDIX) operation under auto-negotiation mode, so standard straight-through twisted-pair
cables can be used to connect to any other network Ethernet module (systems, servers, switches or
routers) that supports auto-negotiation.
NOTE:
Do not plug a phone jack connector into an RJ-45 port. This will damage the Ethernet Switch
Module. Use only twisted-pair cables with RJ-45 connectors that conform to FCC standards.
NOTE:
If autonegotiation is turned off on the ports, a straight through cable must be used.
To connect the Network to the Ethernet Switch Module:
1
Attach a one end of a twisted-pair cable to the Ethernet Switch Module's RJ-45 connector,
and the other end to a switch or server.
2
Make sure each twisted pair cable does not exceed 120 meters (393.7 ft.) in length.
As each connection is made, the green Link LED on the Ethernet Switch Module corresponding to
each port is illuminated indicating that the connection is valid.
For more information see "Port Connections, Cables, and Pinout Information."

External Port Default Settings

NOTE:
Do not connect more than one uplink port to the same switch unless a LAG is being configured.
This is to prevent storming of the network. If more than one port is connected between two switches,
there is a risk that a storming of packets will occur. So the ports are connected in a LAG topology, and
STP is enabled on both ports, there is a risk of storming. The STP prevents such a storm by blocking one
of the ports, therefore preventing any communication in or out of the blocked port.
The general information for configuring the Ethernet Switch Module ports includes the short
description of the auto-negotiation mechanism and the default settings for switching ports.

Auto-Negotiation

Auto-negotiation enables automatic detection of speed, duplex mode and flow control on
switching 10/100/1000 Base-T ports. Auto-negotiation is enabled per port by default.
Auto-negotiation is a mechanism established between two link partners to enable a port to
advertise its transmission rate, duplex mode and flow control (the flow control default is disabled)
abilities to its partner. The ports then both operate at the highest common denominator between
them.
If connecting a Ethernet Switch Module to an external switch port that does not support auto-
negotiation or is not set to auto-negotiation, both the Ethernet Switch Module switching port and
the external switch port must be manually set to the same speed and duplex mode.
If connecting a regular computer NIC (Network Interface Card) to the External Switch Ports, both
should be either configured to Auto Negotiation, or to the same speed and duplex mode, manually.
Meaning, if one of the NIC is configured to 1000/Full Duplex, the same configuration should apply
to the External Switch Port.
Installing the Ethernet Switch Module
37