3Com 5500-SI Switch User Manual


 
544 CHAPTER 26: RSTP CONFIGURATION
In a Switch equipped with the XRN feature, RSTP has the following characteristics:
1) Processing the whole Fabric as a node;
2) Participation of all ports except those used as Fabric ports in role selection;
3) A single root port and bridge id for the whole Fabric;
4) Distributed saving of RSTP port information
RSTP Configuration The configuration of RSTP changes with the position of the Switch in the network, as
discussed below.
Figure 162 Configuring STP
Switch A and Switch B: Root
bridge and backup root
bridge
Switch C and Switch D:
Intermediate Switches in the
Switched network
Switch E, Switch F and Switch
G: Switches directly
connected with user PCs
Table 595 RSTP Configuration
Device Configuration Default Value Note
Switch A
and
Switch B
Enable the STP
feature on the
Switch
Enable the STP
feature on the
port
The STP feature is
disabled from the
Switch, but will be
enabled on all ports
once being enabled
on the Switch.
The configuration of STP feature status on
the port will not take effect if the STP
feature is disabled from the Switch.
Configure RSTP
operational
mode
The Switch works in
RSTP mode.
If there are Switches respectively running
STP and RSTP on the network, it is
recommended to set the Switch in
STP-compatible mode.
Configure the
STP-Ignore
attribute of
VLANs on a
Switch
No VLAN on a
STP-enabled Switch is
STP-Ignored.
Once a VLAN is specified to be STP-Ignored,
the packets of this VLAN will be forwarded
on any Switch port, with no restriction from
the calculated STP path.
Switch C
Switch A
Switch B
Switch D
Switch A
Switch E Switch F Switch G
Switch C
Switch A
Switch B
Switch D
Switch A
Switch E Switch F Switch G