The Cist Screen - ZyXEL Communications GS1900 Series User Manual

Table 118 Configuration > Spanning Tree > STP Port > Edit (continued)
L ABEL
P2P MAC
Migrate
Apply
Cancel
27.2.4 T he C IST Sc re e n
Use this screen to view the
Fig ure 172
The following table describes the labels in this screen.
Table 119 Configuration > Spanning Tree > CIST
L ABEL
CIST Instance
Priority
Max Hops
Forward Delay
Max Age
Tx Hold Count
Hello Time
Apply
Cancel
Chapter 27 Configuration: Spanning Tree
DESC RIPT IO N
Select to activate P2P MAC or
Ye s
Select to activate Migrate or
Ye s
Click to save the changes.
Apply
Click to discard the changes.
C a nc e l
settings. Click
C IST
Configuration > Spanning Tree > CIST
DESC RIPT IO N
Configure priority of CIST bridge ID.
Priority is part of bridge ID, used for CIST root bridge selection.
Enter a maximum number of hops value. The value can be between 1 and 40.
This is the maximum time (in seconds) a switch will wait before changing states. This delay is
required because every switch must receive information about topology changes before it
starts to forward 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 might result. The
allowed range is 4 to 30 seconds.
As a general rule:
2 * (Forward Delay - 1) >= Max Age >= 2 * (Hello Time + 1)
This is the maximum time (in seconds) a switch can wait without receiving a BPDU before
attempting to reconfigure. All switch ports (except for designated ports) should receive BPDUs
at regular intervals. Any port that ages out STP information (provided in the last BPDU) becomes
the designated port for the attached LAN. If it is a root port, a new root port is selected from
among the switch ports attached to the network. The allowed range is 6 to 40 seconds.
Enter a transmission hold count value. The value can be between 1 and 10.
This is the time interval in seconds between BPDU (Bridge Protocol Data Units) configuration
message generations by the root switch. The allowed range is 1 to 10 seconds.
Click to save the changes.
Apply
Click to discard the changes.
C a nc e l
GS1900 Series User's Guide
to deactivate it.
No
to deactivate it.
No
>
C o nfig ura tio n Spa nning T re e
172
> to open this screen.
C IST