Technical data

RackSwitch G8124 Command Reference

 Chapter 2: Information Commands BMD00076, January 2009

The following table describes the CIST parameters.

Table 2-17 CIST Parameter Descriptions

Field Description

CIST Root The CIST Root shows information about the root bridge for the Common

Internal Spanning Tree (CIST). Values on this row of information refer to the

CIST root.

CIST Regional

Root

The CIST Regional Root shows information about the root bridge for this

MSTP region. Values on this row of information refer to the regional root.

Priority

(bridge)

The bridge priority parameter controls which bridge on the network will

become the STP root bridge.

Hello 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.

MaxAge The maximum age parameter specifies, in seconds, the maximum time the

bridge waits without receiving a configuration bridge protocol data unit

before it reconfigure the STP network.

FwdDel 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.

priority (port) The port priority parameter helps determine which bridge port becomes the

designated port/root port. In a network topology that has multiple bridge

ports with the same path-cost connected to a single segment, the port with the

lowest port priority becomes the designated port for the segment.

Cost 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 0 indicates that the cost will be set to the appropriate default after

the link speed has been auto-negotiated.

State The state field shows the current state of the port. The state can be Discard-

ing (DISC), Learning (LRN, or Forwarding (FWD).

Role The Role field 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).

Designated

Bridge

The Designated Bridge shows information about the bridge connected to

each port, if applicable. Information includes the priority (hex) and MAC

address of the Designated Bridge.