IBM Partner Pavilion BMD00082 manual External Trunks, ATrunking External Ports

SmartConnect User’s Guide

External Trunks

When using a VSG with multiple external ports, a trunk can be created between the switch module and another switch. A simple example is shown in Figure 3-A. This provides a virtual link operating at up to 30G per second, depending on how many physical ports are combined.

Switch	Blade	Application Switch
Module	Server
	Chassis

Aggregate

Port Trunk

Figure 3-ATrunking External Ports

The trunk is also useful for connecting a switch module to third-party devices that support link aggregation, such as Cisco routers and switches with EtherChannel technology (not ISL trunk- ing technology) and Sun's Quad Fast Ethernet Adapter. The switch’s trunking technology is compatible with these devices when they are configured manually.

Each VSG can have up to two external port trunks. Each of these trunks may consist of as many external ports as are available in the VSG. By default, the external ports for each VSG are placed into one of the VSG’s available trunks. If all the switch ports belong to the same VSG (as with the factory default configuration), all external ports will be placed into the same trunk, though it is possible that not all links will be active (see “Trunking Rules” on page 32).

Note – Because all external ports in a VSG belong to the same trunk by default, external ports should not be used as regular IEEE 802.3 network links. Do not plug a workstation directly into one of the switch’s active external ports unless it is the only device attached to these ports, or unless the port has been explicitly assigned to a VSG or trunk with no other active external ports.

To reconfigure the trunk assignment for each external port, see “Virtual Switch Groups Mem- bership” on page 97.

BMD00082, February 2009 Chapter 3: Switch Virtualization „ 31