Allied Telesis Rapier Switch - Manual (Page 54)

54 Rapier Switch Software Reference
Software Release 2.5.1
C613-02025-00 REV B
To specify whether the STP will operate in STANDARD mode or RAPID mode,
use the command:
SET STP={stp-name|ALL} [MODE={STANDARD|RAPID}] [other
parameters]
The default is STANDARD. If the mode is changed while the algorithm is
running then the STP is re-initialised.
To display the STP state of the switch ports (Figure 3 on page 61), use the
command:
SHOW STP[={stp-name|ALL}] PORT={port-list|ALL}
A Rapier switch in default LAN configuration has a default Spanning Tree
enabled, spanning only a single default VLAN, to which all ports belong. The
switches in the LAN run a distributed Spanning Tree Algorithm to create a
single Spanning Tree. In a network of Rapier switches with VLANs configured,
all VLANs belong by default to a default Spanning Tree called default. Multiple
Spanning Trees can be created with each Spanning Tree encompassing multiple
VLANs (in networks switched exclusively by Rapier switches).
For more information about multiple spanning trees, see the Switching chapter
in the Rapier Switch Software Reference.
Overlapping VLANs belonging to multiple Spanning
Tree instances
The Rapier i Series switches support the situation where a port is contained in
more than one Spanning Tree instance when the port is a member of more than
one VLAN and those VLANs belong to different STPs (See Figure 1-4 on
page 55).
On the Rapier i Series switches only, the number of STPs that can be configured
is 255.
Table 17: Rapid Spanning Tree port states .
State Meaning
DISABLED STP operations are disabled on the port.
DISCARDING The port does not participate in frame relay. The forwarding
process discards received frames and does not submit
forwarded frames for transmission.
LEARNING The port is enabled for receiving frames only, and the
Learning Process can add new source address information
to the Forwarding Database. The port does not forward any
frames.
FORWARDING The normal state for a switch port. The Forwarding Process
and the Spanning Tree entity are enabled for transmit and
receive operations on the port.