Viewing And Configuring Bridge Instance Details - Motorola RFS Series Reference Manual

4. Refer to the General Configuration
CIST Root
External Root Cost
Regional Root
CIST Bridge Priority
CIST Bridge HelloTime Set the CIST Hello Time (in seconds). After the defined interval all bridges in a
Bridge Hello Time
CIST Bridge Forward
Delay
CIST Bridge Forward
Delay
CIST Bridge Maximum
Age
Bridge Maximum Age Displays the BPDU maximum age value. If this is the root bridge, the value will be

4.10.2 Viewing and Configuring Bridge Instance Details

The Bride Instance tab displays the number of MSTP instance created and VLANS associated with it. To view
and configure the MSTP bridge instance:
1. Select Network
field for the following
This displays the CIST (Common and Internal Spanning Tree) root bridge's bridge
identifier. The bridge identifier consists of a priority value followed by the MAC
address.The lower the path cost, the greater the likelihood of the bridge becoming
the root.
Displays the root cost of the CIST root.
This displays the regional roots MAC address.
Set the bridge priority for the common instance. The value entered, determines the
likelihood this bridge is selected as the root.
The lower the priority the greater the likelihood of the bridge becoming a root.
bridged LAN exchange BPDUs.
The hello time is the time interval (in seconds) the device waits between BPDU
transmissions.
A very low value leads to excessive traffic on the network, whereas a higher value
delays the detection of a topology change. This value is used by all instances.
Displays the configured Hello Time. If this is the root bridge, the value is equal to
the configured Hello Time.
Enter the CIST bridge forward delay value received from the root bridge. If this is
the root bridge, the value will be equal to the Configured Forward Delay.
The forward delay value is the maximum time (in seconds) the root device waits
before changing states (from a listening state to a learning state to a forwarding
state).
This delay is required, as every device must receive information about topology
changes before forwarding frames.
In addition, each port needs time to listen for conflicting information that would
make it return to a blocking state; otherwise, temporary data loops may result.
Displays the configured forward delay period.
Enter the CIST bridge maximum age received from the root bridge. The max-age is
the maximum time (in seconds) for which (if a bridge is the root bridge) a message
is considered valid. This prevents the frames from looping indefinitely. The max-age
should be greater than twice the value of hello time plus one, but less than twice
the value of forward delay minus one. The allowable range for max-age is 6-40
seconds. Configure this value sufficiently high, so a frame generated by root can be
propagated to the leaf nodes without exceeding the maxage.
equal to the Configured Max Age.
> Multiple Spanning Tree from the main menu tree.
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Network Setup