Filter
Top Products
149
Chapter 27 MSTP Commands
MSTP (Multiple Spanning Tree Protocol), compatible with both STP and RSTP and subject to
IEEE 802.1s, can disbranch a ring network. STP is to block redundant links and backup links as
well as optimize paths.
spanning-tree global
Description
The spanning-tree global command is used to configure STP globally. To
return to the default configuration, please use no spanning-tree global
command.
Syntax
spanning-tree global [status {disable | enable}] [mode {stp | rstp | mstp}] [cist
cist] [htime hello-time] [mage max-age] [delay forward-delay] [hcount
hold-count] [mhop max-hops]
no spanning-tree global
Parameter
status —— Enable/ Disable STP function globally. By default, it is disabled.
mode —— STP Version. There are three options, including STP (Spanning Tree
Protocol), RSTP (Rapid Spanning Tree Protocol) and MSTP (Multiple Spanning
Tree Protocol). By default, the STP version is STP.
cist —— CIST Priority, which must be multiple of 4096 ranging from 0 to 61440.
By default, the CIST priority is 32768. CIST Priority is an important criterion on
determining the root bridge. In the same condition, the switch with the highest
priority will be chosen as the root bridge. The lower value has the higher priority.
hello-time —— Hello Time, which is the interval to send BPDU packets, and
used to test the links. Hello Time ranges from 1 to10 in seconds and it is 2 by
default. Otherwise, 2 * (Hello Time + 1) <= Max Age.
max-age —— Max Age, which is the maximum time the switch can wait without
receiving a BPDU before attempting to reconfigure. Max Age ranges from 6 to
40 in seconds. By default, it is 20.
forward-delay —— Forward Delay, which is the time for the port to transit its
state after the network topology is changed. Forward Delay ranges from 4 to 30
in seconds and it is 15 by default. Otherwise, 2 * (Forward Delay - 1) >= Max
Age.