Configuring PVST

Enabling and disabling PVST protection on ports

Syntax:

[no] spanning-tree <port-list> pvst-protection

Enables or disables PVST protection on the ports specified. The command indicates which ports are not expected to receive any PVST BPDUs.

Default: Disabled on all ports.

Enabling PVST protection

To enable the PVST protection feature on ports 4 through 8, enter:

switch(config)#: spanning-tree 4-8 pvst-protection

To disable the PVST protection feature on a port, for example, port 4, enter:

switch(config)#: no spanning-tree 4 pvst-protection

Enabling and disabling PVST filters on ports

Syntax:

[no] spanning-tree <port-list> pvst-filter

Enables or disables PVST filters on the ports specified. The command indicates which ports are not expected to receive any PVST BPDUs.

Default: Disabled on all ports

Enabling PVST filtering on a port

switch(config)#: spanning-tree 8 pvst-filter

Warning: The BPDU filter allows the port to go into a continuous forwarding mode
 and spanning-tree will not interfere, 
even if the port would cause a loop to form in the network topology.
If you suddenly experience high traffic load, disable the port and reconfigure the BPDU filter
 with the CLI command(s):
            "no spanning-tree PORT_LIST bpdu-filter"
            "no spanning-tree PORT_LIST pvst-filter"

Re-enabling a port manually

Syntax:

[no] spanning-tree bpdu-protection-timeout <timeout>

Configures the duration of time protected ports remain disabled. The default value of 0 sets an infinite timeout, so ports that are disabled are not re-enabled automatically.


[NOTE: ]

NOTE: This is a GLOBAL command.


Range: 0 - 65535 seconds; Default: 0

You can also set the timeout in the MIB with this MIB object: hpSwitchStpBpduProtectionTimeout

It is also possible to use the following automatic re-enable timer command:

switch(config)#: spanning-tree bpdu-protection-timeout 120

Displaying ports configured with PVST protection and filtering

Displaying all ports with PVST protection enabled

switch(config)#: show spanning-tree pvst-protection

Status and Counters - PVST Port(s) BPDU Protection Information

BPDU Protection Timeout (sec) : 0
PVST Protected Ports : 5-6

Displaying all ports with PVST filtering enabled

switch(config)#: show spanning-tree pvst-filter
Status and Counters - PVST Port(s) BPDU Filter Information
PVST Filtered Ports : 8

Listing ports to see which have PVST protection or filtering enabled

Syntax:

show spanning-tree <port-list> detail

Displaying if PVST protection is enabled (Yes)