M A G N U M 6 K S W I T C H E S , M N S - 6 K U S E R G U I D E
Designated Root Priority
: 0
Root Bridge Forward Delay
: 15
Root Bridge Hello Time
: 02
Root Bridge Max Age
: 20
Topology Change count
: 0
Time Since topology Chg
: 12
F
IGURE
79
–
Enabling RSTP and reviewing the RSTP variables
The variables listed by the “
show stp config
” command are:
Rapid Spanning Tree Enabled (Global)
: indicates whether STP is enabled or disabled globally
i.e. if the values is YES, all ports have STP enabled, otherwise, all ports have STP disabled
Rapid Spanning Tree Enabled Ports
: indicates which ports have RSTP enabled
Protocol:
indicates type of RSTP protocol active
Bridge Priority
: specifies the switch (bridge) priority value. This value is used along with the
switch MAC address to determine which switch in the network is the root device. Lower values
mean higher priority. Value ranges from 0 to 65535. Default value is 0
Bridge Forward Delay
: indicates the time duration the switch will wait from listening to learning
states and from learning to forwarding states. The value ranges from 4 to 30 seconds. Default
value is 15
Bridge Hello Time
: when the switch is the root device, this is the time between messages being
transmitted. The value is from 1 to 10 seconds. Default value is 2 seconds
Bridge Max Age
: this is the maximum time a message with STP information is allowed by the
switch before the switch discards the information and updates the address table again. Value
ranges from 6 to 40 seconds with default value of 20 seconds
Root Port
: indicates the port number, which is elected as the root port of the switch. A root port
of “0” indicates STP is disabled
Root Path Cost
: a path cost is assigned to individual ports for the switch to determine which
ports are the forwarding points. A higher cost means more loops; a lower cost means fewer loops.
More loops equal more traffic and a tree which takes a long time to converge – resulting in a
slower system
Designated Root
: shows the MAC address of the bridge in the network elected or designated as
the root bridge.
Designated Root Priority
: shows the designated root bridge’s priority. Default value is 0
139