ZyXEL Communications OLT2406, User Manual

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Chapter 14 Spanning Tree Protocol
OLT2406 User’s Guide
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The following table describes the labels in this screen.
Table 41 Advanced Application > Spanning Tree Protocol > MSTP
LABEL DESCRIPTION
Port Click Port to display the MSTP Port screen (see Figure 87 on page 141 ).
Status Click Status to display the MSTP Status screen (see Figure 88 on page 142 ).
Active Select this to activate MSTP on the OLT. Clear this to disable MSTP on the OLT.
Note: You must also activate Multiple Spanning Tree in the Advanced Application >
Spanning Tree Protocol > Configuration screen to enable MSTP on the OLT.
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.
Max Age This is the maximum time (in seconds) the OLT can wait without receiving a BPDU before
attempting to reconfigure. All OLT 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 OLT ports attached to the network. The allowed range is 6 to 40 seconds.
Forwarding Delay This is the maximum time (in seconds) the OLT 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 OLT’s run-time memory. The OLT 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 OLT.
Note: The OLT supports instance numbers 0-16.
Bridge Priority Set the priority of the OLT for the specific spanning tree instance. The lower the number, the
more likely the OLT will be chosen as the root bridge within the spanning tree instance.
Enter priority values between 0 and 61440 in increments of 4096 (thus valid values are 4096,
8192, 12288, 16384, 20480, 24576, 28672, 32768, 36864, 40960, 45056, 49152, 53248, 57344 and
61440).
VLAN Range Enter the start of the VLAN ID range that you want to add or remove from the VLAN range edit
area in the
Start field. Enter the end of the VLAN ID range that you want to add or remove
from the VLAN range edit area in the End field.
Next click:
• Add - to add this range of VLAN(s) to be mapped to the MST instance.
• Remove - to remove this range of VLAN(s) from being mapped to the MST instance.
• Clear - to remove all VLAN(s) from being mapped to this MST instance.
Enabled VLAN(s) This field displays which VLAN(s) are mapped to this MST instance.
Port This field displays the port number. * means all ports.