User guide

4-18
Cisco WLAN Controller Web Interface User Guide
OL-7416-04
Chapter 4 Controller Menu Bar Selection
Controller Spanning Tree Configuration
Command Buttons
• Apply: Data is sent to the controller and made to take effect, but not preserved across a power cycle;
these parameters are stored temporarily in volatile RAM.
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Table 4-12 STP Statistics
Parameter Description
Base MAC Address The MAC address used by this bridge when it must be referred to in a unique
fashion. When concatenated with dot1dStpPriority, a unique BridgeIdentifier
is formed that is used in the Spanning Tree Protocol.
Topology Change
Count
The total number of topology changes detected by this bridge since the
management entity was last reset or initialized.
Time Since Topology
Changed
The time (in days, hours, minutes and seconds) since the last time a topology
change was detected by the bridge entity.
Designated Root The bridge identifier of the root of the spanning tree as determined by the
Spanning Tree Protocol as executed by this node. This value is used as the Root
Identifier parameter in all Configuration Bridge PDUs originated by this node.
Root Port The port number of the port that offers the lowest cost path from this bridge to
the root bridge.
Root Cost The cost of the path to the root as seen from this bridge.
Max Age (seconds) The maximum age of Spanning Tree Protocol information learned from the
network on any port before it is discarded.
Hello Time (seconds) The amount of time between the transmission of Configuration Bridge PDUs
by this node on any port when it is the root of the spanning tree or trying to
become so. This is the actual value that this bridge is currently using.
Forward Delay
(seconds)
This time value controls how fast a port changes its spanning state when
moving towards the Forwarding state. The value determines how long the port
stays in each of the Listening and Learning states, that precede the Forwarding
state. This value is also used, when a topology change has been detected and is
underway, to age all dynamic entries in the Forwarding Database. [This value
is the one that this bridge is currently using, in contrast to Stp Bridge Forward
Delay that is the value that this bridge and all others would start using if/when
this bridge were to become the root.]
Hold Time (seconds) The minimum time period to elapse between the transmission of Configuration
BPDUs through a given LAN Port: at most one Configuration BPDU shall be
transmitted in any Hold Time period.