ZyXEL Communications GS2200 Series, Руководство пользователя

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Chapter 13 Spanning Tree Protocol
GS2200 Series User’s Guide
112
13.7 Multiple Rapid Spanning Tree Protocol Status
Click Advanced Application > Spanning Tree Protocol in the navigation panel to display the
status screen as shown next. See
Section 13.1 on page 103 for more information on MRSTP.
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)
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.
Active Select this check box to activate STP on this port.
Edge Select this check box to configure a port as an edge port when it is directly attached to
a computer. An edge port changes its initial STP port state from blocking state to
forwarding state immediately without going through listening and learning states right
after the port is configured as an edge port or when its link status changes.
Note: An edge port becomes a non-edge port as soon as it receives a Bridge Protocol
Data Unit (BPDU).
Priority Configure the priority for each port here.
Priority decides which port should be disabled when more than one port forms a loop in
a switch. Ports with a higher priority numeric value are disabled first. The allowed range
is between 0 and 255 and the default value is 128.
Path Cost Path cost is the cost of transmitting a frame on to a LAN through that port. It is
recommended to assign this value according to the speed of the bridge. The slower the
media, the higher the cost-see
Table 27 on page 104 for more information.
Tree Select which STP tree configuration this port should participate in.
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.
Table 32
Advanced Application > Spanning Tree Protocol > MRSTP (continued)
LABEL DESCRIPTION