ZyXEL Communications GS2210 Series User Manual page 134

Table 53 Advanced Application > Spanning Tree Protocol > MSTP (continued)
LABEL DESCRIPTION
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 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) the 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 0-15.
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.
Port This field displays the port number.
* Settings in this row apply to all ports.
Use this row only if you want to make some settings the same for all ports. Use this row
first to set the common settings and then make adjustments on a port-by-port basis.
Note: Changes in this row are copied to all the ports as soon as you make them.
Chapter 13 Spanning Tree Protocol
GS2210 Series User's Guide
134