Cabletron Systems SmartStack STS16-20FRM, Installation And User Manual

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SmartStack STS16-20RM/STS16-20FRM Token Ring Switches, P/N: 9032957-01 Switch Configuration
The port with the lowest number configured in the CrossLink is called the base port.
The active port with the lowest number is selected as the primary port. The
CrossLink software learns addresses differently than regular ports, as follows:
•
New source address. When a packet arrives at a CrossLink port with an
unknown source address, the system module creates an entry in the master
table and the port table for the CrossLink. The system module assigns the
primary port in the CrossLink as the location of the address.
For additional source addresses, the system module assigns locations
alternately to other ports in the CrossLink. When all ports in the CrossLink
have at least one address assigned, the system module starts assigning from the
primary port again.
•
New destination address. An unknown destination address packet is sent out
on the primary ports of the CrossLink, but entries are not made in ports tables
until a reply packet comes back. Entries in port tables depend upon the
destination. See the description of primary ports on page 113.
•
Broadcast and multicast packets. Broadcast and multicast packets go to the
primary port of each CrossLink.
•
Link failure. If one link in a CrossLink fails, a trap is sent, and the CrossLink
connection continues with the rest of the links. If the link that is going down is
the primary port, a new primary port will be selected instead.