Dell S6000-ON, Configuration Manual

Page: 767 / 1080

To view the current values for interface parameters, use the
show spanning-tree rstp
command
from EXEC privilege mode.
Enabling SNMP Traps for Root Elections and Topology
Changes
To enable SNMP traps collectively, use this command.
Enable SNMP traps for RSTP, MSTP, and PVST+ collectively.
snmp-server enable traps xstp
Influencing RSTP Root Selection
RSTP determines the root bridge, but you can assign one bridge a lower priority to increase the likelihood
that it is selected as the root bridge.
To change the bridge priority, use the following command.
• Assign a number as the bridge priority or designate it as the primary or secondary root.
PROTOCOL SPANNING TREE RSTP mode
bridge-priority priority-value
–
priority-value
The range is from 0 to 65535. The lower the number assigned, the more likely
this bridge becomes the root bridge.
The default is 32768 . Entries must be multiples of 4096.
Example of the bridge-priority Command
A console message appears when a new root bridge has been assigned. The following example example
shows the console message after the
bridge-priority
command is used to make R2 the root bridge
(shown in bold).
Dell(conf-rstp)#bridge-priority 4096
04:27:59: %RPM0-P:RP2 %SPANMGR-5-STP_ROOT_CHANGE: RSTP root changed. My Bridge
ID:
4096:0001.e80b.88bd Old Root: 32768:0001.e801.cbb4 New Root: 4096:0001.e80b.88bd
Configuring an EdgePort
The EdgePort feature enables interfaces to begin forwarding traffic approximately 30 seconds sooner.
In this mode an interface forwards frames by default until it receives a BPDU that indicates that it should
behave otherwise; it does not go through the Learning and Listening states. The
bpduguard shutdown-
on-violation
option causes the interface hardware to be shut down when it receives a BPDU. When
only
bpduguard
is implemented, although the interface is placed in an Error Disabled state when
receiving the BPDU, the physical interface remains up and spanning-tree drops packets in the hardware
after a BPDU violation. BPDUs are dropped in the software after receiving the BPDU violation. This feature
is the same as PortFast mode in Spanning Tree.
CAUTION: Configure EdgePort only on links connecting to an end station. If you enable EdgePort
on an interface connected to a network, it can cause loops.
Dell Networking OS Behavior : Regarding bpduguard shutdown-on-violation behavior:
• If the interface to be shut down is a port channel, all the member ports are disabled in the hardware.
Rapid Spanning Tree Protocol (RSTP)
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