Configurable Port Types; The Difference Between Lattisspan Trunk And Feeder Ports - Bay Networks BayStack 281 Series Manual

Configurable Port Types

The Difference Between LattisSpan Trunk and Feeder Ports

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For more information about the maximum allowable number of "hops"
between BayStack 281xx switches in a community, see
Between End Stations" later in this chapter.
You can set up redundant connections for shared media segments connecting
servers and hosts through configurable redundant feeder ports. This capability
is provided through the configurable port types feature of the BayStack 281xx
switch.
Without configurable port types, the software considers multiple switch ports
that are connected to a common Ethernet segment (for example, an Ethernet
repeater) as trunk ports. End stations connected to trunk ports on a common
Ethernet segment are not recognized by the switch.
The configurable port types feature provides complete port and switch level
redundancy within one or more switch communities. You can configure the
switch port type either through the Switch Port Type user interface screen or
through a Simple Network Management Protocol (SNMP) request. For more
information about configuring the switch port through the Switch Port Type
user interface screen, see "Modifying Switch Port Type" on page 4-17.
Using the switch port types feature, you can configure the ports in the
BayStack 281xx switch to operate in one of two modes: automatic (auto) mode
or forced feeder (feeder) mode. All ports are preconfigured, by default, to
operate in auto mode. Auto ports use the LattisSpan trunk detection process to
configure the port automatically as a LattisSpan trunk port or feeder port. These
ports operate differently, and it is important to understand the difference
between the ports before configuring them to operate in auto or feeder mode.
The link that connects LattisSpan trunk ports is a LattisSpan trunk link.
Such a link carries traffic for multiple virtual LANs between switches and
shares station MAC addresses between connected switches. Trunk ports do not
learn addresses of the individual end stations connected to the port. In addition,
if an Ethernet segment is used as a trunk link between two switches, the
switches will not learn the addresses of any end stations attached to the
segment. This means there is no connectivity to those end stations on that
segment. A LattisSpan trunk link joins the switches at each end of the link into
a single switch community.
BayStack 281xx Switch Operation
"Seven-switch Limit
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