GE MultiLink ML1200 Instruction Manual page 215

CHAPTER 13: RAPID SPANNING TREE PROTOCOL
Example 13-3: RSTP information from a network with multiple switches
show stp ports
ML1200(rstp)##
RSTP Port Configuration
-------------------------------------------------------------------------------
Port# Type Priority
-------------------------------------------------------------------------------
01 TP(10/100)
02 TP(10/100)
03 100MB Fiber
04 100MB Fiber
05 100MB Fiber
MULTILINK ML1200 MANAGED FIELD SWITCH – INSTRUCTION MANUAL
Path Cost State
128 200000 Forwarding
128 2000000 Disabled
128 200000 Disabled
128 200000 Disabled
128 200000 Disabled
• Path Cost: This is the assigned port cost value used for the switch to determine the
forwarding points. Values range from 1 to 2000000. Lower values indicate a lower
cost and hence the preferred route. The costs for different Ethernet speeds are
indicated below. The Path cost in STP is compared to the path cost in RSTP.
Table 13–1: Path cost as defined in IEEE 802.1d / 802.1w
10 Mbps
100 Mbps
1 Gbps
10 Gbps
• State: Indicates the STP state of individual ports. Values can be Listening, Learning,
Forwarding, Blocking and Disabled.
• Des. Bridge: This is the port's designated root bridge
• Des. Port: This is the port's designated root port
Another example of the same command, from a larger network with several switches is
shown in Example 13-3. Note the
manager level prompt or from RSTP configuration state as shown in the screen captures
earlier
In this example, ports 9 and 10 have a path cost of 20000 and are the least cost paths.
These ports are connected to other switches and the ports are enabled as forwarding
ports. Ports 6 and 7 are also connected to other switches. From the state column, it
indicates that port 7 is in a standby state as that port is discarding all traffic.
More CLI commands associated with RSTP in the RSTP configuration mode are shown
below. The
forceversion
forceversion <stp|rstp>
The
show-forceversion
show-forceversion
Des. Bridge
80:00:00:20:06:30:00:01
Port type STP path cost
100
19
4
2
show stp ports
command sets the STP or RSTP compatibility mode.
command displays the current forced version.
RAPID SPANNING TREE PROTOCOL
Des. Port
00:01
00:02
00:03
00:04
00:05
RSTP path cost
2000000
200000
20000
2000
command can be executed from the
13–7