D-Link xStack DGS-3426 User Manual - page 112
xStack DGS-3400 Series Fast Ethernet Switch
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) <2>
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) <20>
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)
<15 >
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.
Max Hops (1-20) <20>
Used to set the number of hops between devices in a spanning tree region
before the BPDU (bridge protocol data unit) packet sent by the Switch will be
discarded. Each switch on the hop count will reduce the hop count by one until
the value reaches zero. The Switch will then discard the BDPU packet and the
information held for the port will age out. The user may set a hop count from 1
to 20. The default is 20.
TX Hold Count (1-10) <3>
Used to set the maximum number of Hello packets transmitted per interval.
The count can be specified from 1 to 10. The default is 3.
Forwarding BPDU
This field can be Enabled or Disabled. When Enabled, it allows the forwarding
of STP BPDU packets from other network devices. The default is Enabled.
Loopback Guard
When enabled, the Switch will temporarily block STP switch-wide when a
BDPU packet has looped back. If the Switch detects its own BDPU packet
coming back, it signifies a loop on the network – STP is automatically blocked
and an alert is sent to the administrator. The default is Enabled.
LBD Auto Recover <60>
Time allowed (in seconds) for recovery when an STP loopback is detected.
After the timer has expired the Switch checks for an STP loopback, if no
loopback detected, STP is resumed. Entering 0 will disable LDB recovery.
Click Apply to implement changes made.
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