6
STP, RSTP, and MSTP configuration and management
Specifying the port-channel path cost
In any mode (STP, RSTP, or MSTP), use this command to specify the port-channel path cost. The
default port cost is standard. The path cost options are:
•
•
To specify the port-channel path cost, perform the following steps from Privileged EXEC mode.
1. Enter the configure terminal command to access global configuration mode.
2. Enter the protocol command to enable STP, RSTP, or MSTP.
3. Specify the port-channel path cost.
Specifying the bridge hello time (STP and RSTP)
In STP or RSTP mode, use this command to configure the bridge hello time. The hello time
determines how often the switch interface broadcasts hello Bridge Protocol Data Units (BPDUs) to
other devices.The range is 1 through 10 seconds. The default is 2 seconds.
When configuring the hello-time, the max-age setting must be greater than the hello-time setting.
The following relationship should be kept:
2*(forward_delay - 1)>=max_age>=2*(hello_time + 1)
To specify the bridge hello time, perform the following steps from Privileged EXEC mode.
1. Enter the configure terminal command to access global configuration mode.
2. Enter the protocol command to enable STP, RSTP, or MSTP.
3. Specify the time range in seconds for the interval between the hello BPDUs sent on an
Specifying the transmit hold count (RSTP and MSTP)
In RSTP and MSTP mode, use this command to configure the BPDU burst size by specifying the
transmit hold count value. The command configures the maximum number of BPDUs transmitted
per second for RSTP and MSTP before pausing for 1 second. The range is 1 through 10. The default
is 6 seconds.
To specify the transmit hold count, perform the following steps from Privileged EXEC mode.
1. Enter the configure terminal command to access global configuration mode.
2. Specify the transmit hold count.
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custom—Specifies that the path cost changes according to the port-channel's bandwidth.
standard—Specifies that the path cost does not change according to the port-channel's
bandwidth.
switch(config)#protocol spanning-tree stp
switch(conf-stp)#port-channel path-cost custom
switch(config)#protocol spanning-tree stp
interface.
switch(conf-stp)#hello-time 5
switch(config)#transmit-holdcount 5
Dell Converged Enhanced Ethernet Administrator's Guide
53-1002116-01