Planet IGSW-2840, User Manual

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User’s Manual of IGSW-2840
159
The page includes the following fields:
Object Description
•
Hello Time
Interval (in seconds) at which the root device transmits a configuration message.
-Default: 2
-Minimum: 1
-Maximum: The lower of 10 or [(Max. Message Age / 2) -1]
•
Maximum Age
The maximum time (in seconds) a device can wait without receiving a
configuration message before attempting to reconfigure. All device ports (except
for designated ports) should receive configuration messages at regular intervals.
Any port that ages out STA information (provided in the last configuration
message) becomes the designated port for the attached LAN.
If it is a root port, a new root port is selected from among the device ports
attached to the network. (References to “ ports ” in this section mean “interfaces,”
which includes both ports and trunks.)
-Default: 20
-Minimum: The higher of 6 or [2 x (Hello Time + 1)].
-Maximum: The lower of 40 or [2 x (Forward Delay -1)]
•
Forward Delay The maximum time (in seconds) this device will wait before changing states (i.e.,
discarding to learning to forwarding). This delay is required because every device
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 discarding state; otherwise, temporary data loops might
result.
-Default: 15
-Minimum: The higher of 4 or [(Max. Message Age / 2) + 1]
-Maximum: 30
■
Configuration Settings for RSTP
The following attributes apply to both RSTP and MSTP:
Figure 4-7-4 RSTP Configuration screenshot