Alcatel Carrier Internetworking Solutions Omni Switch/Router - Manual (Page 472)

Configuring Spanning Tree
Page 17-24
• IBM SRT bridges send an IEEE-style STE RIF over Token Ring networks. The Omni
Switch/Router does not support this frame, and any frame of this type received by the
switch is discarded.
• The OmniSwitch/Router does not support using the same Functional Address (FA) for both
data and spanning tree frames. The FA for IBM Spanning Tree is programmed into the
MPX CAM, and all data frames with this FA are claimed by the MPX. Therefore, any data
with the same FA as the IBM Spanning Tree FA will not be able to pass through the
switch. There are two workarounds for this situation:
– If you are not using IBM Spanning Tree and you want to prevent the specific
FA from being programmed into the MPX CAM, then enter the command
faBpGrpDisable into the mpx.cmd file, before the cmInIt command, with a
value of 1.
– If you are using IBM Spanning Tree and need the FA (0300 0000 0800), and
you are using all Alcatel equipment (or other third party switch that allows
you to change the IBM Spanning Tree FA), you can enter the command
faBpGrpOverride into the mpx.cmd file with a new value for the lower 32-bit
part of the address (0000 0800).
♦ Note ♦
If you change a group to IBM Spanning Tree, all non-
Token Ring ports are put into manual forwarding state.
Messages are displayed indicating these port state
changes; in addition, SNMP traps are sent to indicate
these changes. (Manual forwarding state is where the
port is put into forwarding state and the Spanning Tree
algorithm is disabled.) Token Ring ports will be set to
use functional addresses.
The following sections provide specific information on using the spanning tree commands.