ZyXEL XGS4700-48F User Guide - Page 165

Table 33, Multiple Spanning Tree, Advanced Application > Spanning Tree Protocol &gt,

Page 165 highlights

Chapter 13 Spanning Tree Protocol The following table describes the labels in this screen. Table 33 Advanced Application > Spanning Tree Protocol > MSTP LABEL DESCRIPTION Status Click Status to display the MSTP Status screen (see Figure 74 on page 168). Active Select this check box to activate MSTP on the Switch. Clear this checkbox to disable MSTP on the Switch. Hello Time MaxAge Forwarding Delay Note: You must also activate Multiple Spanning Tree in the Advanced Application > Spanning Tree Protocol > Configuration screen to enable MSTP on the Switch. 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. 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. 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: Maximum hops Configuration Name Revision Number Apply Cancel Instance Instance Note: 2 * (Forward Delay - 1) >= Max Age >= 2 * (Hello Time + 1) Enter the number of hops (between 1 and 255) in an MSTP region before the BPDU is discarded and the port information is aged. Enter a descriptive name (up to 32 characters) of an MST region. Enter a number to identify a region's configuration. Devices must have the same revision number to belong to the same region. Click Apply to save your changes to the Switch's run-time memory. The Switch loses these changes if it is turned off or loses power, so use the Save link on the top navigation panel to save your changes to the nonvolatile memory when you are done configuring. Click Cancel to begin configuring this screen afresh. Use this section to configure MSTI (Multiple Spanning Tree Instance) settings. Enter the number you want to use to identify this MST instance on the Switch. The Switch supports instance numbers 0-16. XGS4700-48F User's Guide 165

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Chapter 13 Spanning Tree Protocol
XGS4700-48F User’s Guide
165
The following table describes the labels in this screen.
Table 33
Advanced Application > Spanning Tree Protocol > MSTP
LABEL
DESCRIPTION
Status
Click
Status
to display the
MSTP Status
screen (see
Figure 74 on page
168
).
Active
Select this check box to activate MSTP on the Switch. Clear this
checkbox to disable MSTP on the Switch.
Note: You must also activate
Multiple Spanning Tree
in the
Advanced Application > Spanning Tree Protocol >
Configuration
screen to enable MSTP on the Switch.
Hello Time
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.
MaxAge
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.
Forwarding
Delay
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:
Note: 2 * (Forward Delay - 1) >= Max Age >= 2 * (Hello Time + 1)
Maximum hops
Enter the number of hops (between 1 and 255) in an MSTP region
before the BPDU is discarded and the port information is aged.
Configuration
Name
Enter a descriptive name (up to 32 characters) of an MST region.
Revision
Number
Enter a number to identify a region’s configuration. Devices must have
the same revision number to belong to the same region.
Apply
Click
Apply
to save your changes to the Switch’s run-time memory. The
Switch loses these changes if it is turned off or loses power, so use the
Save
link on the top navigation panel to save your changes to the non-
volatile memory when you are done configuring.
Cancel
Click
Cancel
to begin configuring this screen afresh.
Instance
Use this section to configure MSTI (Multiple Spanning Tree Instance)
settings.
Instance
Enter the number you want to use to identify this MST instance on the
Switch. The Switch supports instance numbers 0-16.