Allied Telesis C613-02013-00 manual Port Trunking, Autonegotiation preferences for Ethernet ports

30 Rapier Switch User Guide

which speed and mode to use. Autonegotiation allows the ports to adjust their speed and duplex mode to accommodate the devices connected to them. Each switch port can be either configured with a fixed speed and duplex mode, or configured to autonegotiate speed and duplex mode with a device connected to it to determine a speed and mode that will allow successful transmission. An autonegotiating port will adopt the speed and duplex mode required by devices connected to it. If another autonegotiating device is connected to the switch, they will negotiate the highest possible common speed and duplex mode (Table 4). Setting the port to a fixed speed and duplex mode allows it to support equipment that cannot autonegotiate. Switch ports will autonegotiate by default when they are connected to a new device. To change this setting, use the command:

SET SWITCH PORT={port-listALL} SPEED={AUTONEGOTIATE10MHALF10MFULL100MHALF100MFULL10 00MHALF1000MFULL}

Autonegotiation can also be activated at any time after this, on any port that is set to autonegotiate, by using the command:

ACTIVATE SWITCH PORT={port-listALL} AUTONEGOTIATE

On the first switch, the gigabit uplink ports always use 1000 Mbps speed and operate in full duplex mode, but these ports can also autonegotiate with peers in order to successfully pass the negotiation phase to get to successful operation.

Table 4: Autonegotiation preferences for Ethernet ports

Preference	10/100 Ethernet switch ports		Gigabit Ethernet uplink ports
Highest	100	Mbps, Full duplex	1000Mbps Full duplex
	100	Mbps, Half duplex
	10Mbps, Full duplex
Lowest	10Mbps, Half duplex

The SHOW SWITCH PORT command displays the port speed and duplex mode settings.

Port Trunking

Port trunking, also known as port bundling or link aggregation, allows a number of ports to be configured to join together to make a single logical connection of higher bandwidth. This can be used where a higher performance link is required, and makes links even more reliable.

The switch supports up to 6 trunk groups, of up to 8 switch ports each. The two gigabit Ethernet ports can also be grouped together to form a trunk group. It is not possible for a trunk group to include both 10/100 Ethernet and gigabit Ethernet ports. Ports in the trunk group do not have to be contiguous. Port trunking is supported between AR800 Series and Rapier switches, and may be compatible with trunking algorithms on third party devices.

Port trunk groups are created and destroyed on the switch using the commands:

CREATE SWITCH TRUNK=trunk [PORT=port-list]

[SELECT={MACSRCMACDESTMACBOTHIPSRCIPDESTIPBOTH}]

[SPEED={10M100M1000M}]

Rapier Switch Software Release 2.2.1 C613-02013-00 Rev A