D-Link xStack DGS-3426, User Manual

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xStack DGS-3400 Series Layer 2 Gigabit Ethernet Managed Switch
Figure 7- 38. STP Bridge Global Settings – STP Compatible
See the table below for descriptions of the STP versions and corresponding setting options.
NOTE: The Hello Time cannot be longer than the Max. Age. Otherwise, a configuration error will
occur. Observe the following formulas when setting the above parameters:
Max. Age <= 2 x (Forward Delay - 1 second)
Max. Age <= 2 x (Hello Time + 1 second)
Configure the following parameters for STP:
Parameter Description
STP Status
Use the pull-down menu to globally enable or disable STP.
STP Version Use the pull-down menu to choose the desired version of STP:
STP
- Select this parameter to set the Spanning Tree Protocol (STP) globally on the
switch.
RSTP
- Select this parameter to set the Rapid Spanning Tree Protocol (RSTP) globally on
the Switch.
MSTP
- Select this parameter to set the Multiple Spanning Tree Protocol (MSTP) globally
on the Switch.
Hello Time (1 - 10 Sec) The Hello Time can be set from
1
to
10
seconds. This is the interval between two
transmissions of BPDU packets sent by the Root Bridge to tell all other switches that it is
indeed the Root Bridge. This field will only appear here when STP or RSTP is selected for
the STP Version. For MSTP, the Hello Time must be set on a port per port basis. See the
MST Port Settings section for further details.
Max Age (6 - 40 Sec) The Max Age may be set to ensure that old information does not endlessly circulate
through redundant paths in the network, preventing the effective propagation of the new
information. Set by the Root Bridge, this value will aid in determining that the Switch has
spanning tree configuration values consistent with other devices on the bridged LAN. If the
value ages out and a BPDU has still not been received from the Root Bridge, the Switch
will start sending its own BPDU to all other switches for permission to become the Root
Bridge. If it turns out that your switch has the lowest Bridge Identifier, it will become the
Root Bridge. The user may choose a time between
6
and
40
seconds. The default value is
20
.
Forward Delay (4 - 30
sec) The Forward Delay can be from
4
to
30
seconds. Any port on the Switch spends this time
in the listening state while moving from the blocking state to the forwarding state.
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