HP 438031-B21 - 1:10Gb Ethernet BL-c Switch Cli Reference Manual page 39

Role
Designated bridge and port
Link type
The following table describes the STP parameters in RSTP or MSTP mode.
Table 24 Rapid Spanning Tree parameter descriptions
Parameter
Current Root
Path-Cost
Port
Priority (bridge)
Hello
MaxAge
FwdDel
Aging
Priority (port)
Cost
State
Role
Designated bridge
Designated port
Description
Shows information about the root bridge for the Spanning Tree. Information includes
the priority (hex) and MAC address of the root.
Path-cost is the total path cost to the root bridge. It is the summation of the path cost
between bridges (up to the root bridge).
The current root port refers to the port on the switch that receives data from the current
root. Zero (0) indicates the root bridge of the STP.
The bridge priority parameter controls which bridge on the network will become the
STP root bridge.
The hello time parameter specifies, in seconds, how often the root bridge transmits a
configuration bridge protocol data unit (BPDU). Any bridge that is not the root bridge
uses the root bridge hello value.
The maximum age parameter specifies, in seconds, the maximum time the bridge waits
without receiving a configuration bridge protocol data unit before it reconfigures the
STP network. If the bridge is not the root bridge, it uses the MaxAge value of the root
bridge.
The forward delay parameter specifies, in seconds, the amount of time that a bridge
port has to wait before it changes from learning state to forwarding state. If the bridge
is not the root bridge, it uses the FwdDel value of the root bridge.
The aging time parameter specifies, in seconds, the amount of time the bridge waits
without receiving a packet from a station before removing the station from the
Forwarding Database.
The port priority parameter helps determine which bridge port becomes the designated
port. In a network topology that has multiple bridge ports connected to a single
segment, the port with the lowest port priority becomes the designated port for the
segment.
The port path cost parameter is used to help determine the designated port for a
segment. Generally speaking, the faster the port, the lower the path cost. A setting of
zero (0) indicates that the cost will be set to the appropriate default after the link speed
has been auto-negotiated.
Shows the current state of the port. The State field in RSTP/MSTP mode can be one of
the following: Discarding (DISC), Learning (LRN), Forwarding (FWD), or Disabled
(DSB).
Shows the current role of this port in the Spanning Tree. The port role can be one of the
following: Designated (DESG), Root (ROOT), Alternate (ALTN), Backup (BKUP), Master
(MAST), or Unknown (UNK).
Shows information about the bridge connected to each port, if applicable. Information
includes the priority (hex) and MAC address of the Designated Bridge.
The port ID of the port on the Designated Bridge to which this port is connected.
Information Commands
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