ZyXEL Communications MES3500-24S User Manual page 139

The following table describes the labels in this screen.
Table 46 Advanced Application > Spanning Tree Protocol > MSTP
LABEL DESCRIPTION
Port Click Port to display the MSTP Port Configuration screen (see
Status Click Status to display the MSTP Status screen (see
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 >
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 Enter a descriptive name (up to 32 characters) of an MST region.
Name
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 0-64 for the MGS320 Series, and 0-32 for the MES3500-24S.
Bridge Priority Set the priority of the Switch for the specific spanning tree instance. The lower the number, the
more likely the Switch 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.
Chapter 13 Spanning Tree Protocol
Spanning Tree Protocol > Configuration screen to enable MSTP on the Switch.
MES3500-24S/MGS3520 Series User's Guide
139
Figure 77 on page
Figure 78 on page 142).
141).