Multiple Rapid Spanning Tree Protocol Status - ZyXEL Communications XS3800-28 User Manual

Table 77 Advanced Application > Spanning Tree Protocol > MRSTP (continued)
LABEL
Forwarding Delay
SLOT
Port
*
Active
Edge
Root Guard
Priority
Path Cost
Tree
Apply
Cancel

13.9 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
Chapter 13 Spanning Tree Protocol
DESCRIPTION
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)
This field appears only in stacking mode. Click the drop-down list to choose the slot number of
the Switch in a stack.
This field displays the port number. In stacking mode, the first number represents the slot ID and
the second is the port number. Please note that the default stacking ports (the last four ports
of your Switch) cannot be configured. They are reserved for stacking only.
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.
Select this check box to activate STP on this port.
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).
Select this check box to enable root guard on this port in order to prevent the switch(es)
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.
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 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.
Select which STP tree configuration this port should participate in.
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.
Click Cancel to begin configuring this screen afresh.
Section 13.9 on page 200
XS3800-28 User's Guide
200
for more information on MRSTP.