ZyXEL Communications GS2220-10, Руководство пользователя

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GS2220 Series User’s Guide
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13.6 Configure Multiple Spanning Tree Protocol
To configure MSTP, click MSTP in the Advanced Application > Spanning Tree Protocol screen.
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:
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 RSTP 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).
Root Guard Select this check box to enable root guard on this port in order to prevent the switches
attached to the port from becoming the root bridge.
With root guard enabled, a port is blocked when the Switch receives a superior BPDU on it. The
Switch allows traffic to pass through this port again when the switch connected to the port
stops to send superior BPDUs.
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.
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 67 Advanced Application > Spanning Tree Protocol > RSTP (continued)
LABEL DESCRIPTION