Ethernet Switch User Manual
Manual_cmd_line_config-ESML6-P3-Rev1106
Copyright © KBC Networks Ltd.
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11
RSTP configuration
11.1
Introduction
RSTP (Rapid Spanning Tree Protocol) is a Layer 2 management protocol developed from
STP (Spanning Tree Protocol) it is compatible with STP and has all the functionality of
STP but is quicker. RSTP defines the Root Bridge, Root Port, Designated Port, Path Cost
and ensures that there are no active network loops. By creating a tree topology it also
optimizes the link backup and path selection.
The ESML6-P3 series fully supports RSTP and STP and can also be connected with other
devices which support STP. Single ports can be enabled or disabled, STP edge-ports can
be disabled to avoid causing a block status when the network topology is changed.
11.2
RSTP configuration
11.2.1
RSTP bridge node
Enable RSTP :
SWITCH(config)#rstp enable
Disable RSTP:
SWITCH(config)#rstp disable
Bridge priority:
SWITCH(config)#rstp bridge priority <0x00-0xFFFF>
Where <0x00-0xFFFF> is the value of the bridge priority. Its range is 0x00 to 0xFFFF,
the pace is 0x1000, default value is 0x8000.
The device’s bridge priority and MAC address compose the bridge ID. RSTP determines
the current root bridge and root port by the bridge ID. The lower the number of the
priority the higher the priority the bridge will have. The device with the smallest bridge
ID will be regarded as the root bridge.
In the network, the device with the lowest priority setting will be forced to be the root
bridge.
Setting bridge forward delay:
SWITCH(config)#rstp forward-delay <4-30>
Where <4-30>is the forward delay in seconds. The default value is 15 seconds.
The forward delay is the status transition time for Discarding -> Learning -> Forwarding.
It is set by the ROOT and it is the same for the whole network. This delay time also
includes the MAC address table’s Short Ageing Time.
Setting bridge hello time:
SWITCH(config)#rstp hello-time <1-2>
