Spanning Tree HP-Switch (Config)#spanning-tree (Turns on Spanning Tree) HP-Switch (Config)#spanning-tree priority 0 (Makes this switch the root switch with a priority of 4096) HP-Switch (Config)#spanning-tree force-version rstp-operation (Operates. Multiple Instance Spanning-Tree Operation 802.1s Multiple Spanning Tree Protocol (MSTP) For example, to configure BPDU filtering on port a9, enter: ProCurve(config)# spanning-tree a9 bpdu-filter Viewing BPDU Filtering. The spanning-tree show configuration command displays the BPDU’s filter state. By default, Cisco’s Per-VLAN Spanning-Tree plus (PVST+) adds this system ID extension (sys-id-ext) to the bridge priority. The 48 bit (6-byte) MAC address of a switch is used in conjunction with the bridge priority value and the system ID extension as criteria for the root bridge election.

• Hp Procurve Spanning Tree Port Priority
• Procurve Spanning Tree Priority Boxes
• Procurve Spanning Tree Priority Code

When you enable MSTP on the switch, a spanning tree instance is enabled automatically. The switch supports up to 16 configurable MST instances for each VLAN group that you want to operate as an active topology within the region to which the switch belongs. When creating an instance, you must include a minimum of one VID. You can add more VIDs later if desired.

IMPORTANT:When the HP 2920 Switch is configured in a stack, the amount of configurable MSTIs is limited to four. If stacking is enabled and a fifth MSTI is created, an error will occur. However, when the HP 2920 Switch is configured as a standalone, a maximum of 16 MSTIs is supported.

Syntax:

[no] spanning-tree instance <1..4> vlan <vid> [<vid..vid>]

Configuring MSTP on the switch automatically configures the IST instance and places all statically and dynamically configured VLANs on the switch into the IST instance. This command creates a new MST instance (MSTI) and moves the VLANs you specify from the IST to the MSTI.

You must map at least one VLAN to an MSTI when you create it. You cannot map a VLAN ID to more than one instance. You can create up to 16 MSTIs in a region.

The no form of the command removes one or more VLANs from the specified MSTI. If no VLANs are specified, the no form of the command deletes the specified MSTI.

When you remove a VLAN from an MSTI, the VLAN returns to the IST instance, where it can remain or be re-assigned to another MSTI configured in the region.

NOTE: You can enter the spanning-tree instance vlan command before a static or dynamic VLAN is configured on the switch to preconfigure VLAN ID-to-MSTI mappings. No error message is displayed. Later, each newly configured VLAN that has already been associated with an MSTI is automatically assigned to the MSTI.

This new default behavior differs from automatically including configured (static and dynamic) VLANs in the IST instance and requiring the manual assigning of individual static VLANs to an MSTI.

NOTE: The valid VLAN IDs that you can map to a specified MSTI are from 1 to 4094. The VLAN ID-to-MSTI mapping does not require a VLAN to be already configured on the switch. The MSTP VLAN enhancement allows you to preconfigure MSTP topologies before the VLAN IDs associated with each instance exist on a switch.

Syntax:

spanning-tree instance <1..4> priority <priority-multiplier>

Sets the switch (bridge) priority for the designated instance. This priority is compared with the priorities of other switches in the same instance to determine the root switch. The lower the priority value, the higher the priority. If there is only one switch in the instance, then that switch is the root switch for the instance. The IST regional root bridge provides the path to instances in other regions that share one or more of the same VLANs.

The priority range for an MSTP switch is 0 - 61440. However, this command specifies the priority as a multiplier (0 - 15) of 4096. When a priority multiplier value is set from 0 - 15, the actual priority assigned to the switch for the specified MST instance is: (priority-multiplier) x 4096

For example, if you configure 5 as the priority-multiplier for MST Instance 1 on a given MSTP switch, the Switch Priority setting is 20,480 for that instance in that switch.

NOTE: If multiple switches in the same MST instance have the same priority setting, the switch with the lowest MAC address becomes the root switch for that instance.

Syntax:

spanning-tree instance <ist | 1..4> <port-list> path-cost [auto | <1..200000000>]

Assigns an individual port cost for the IST or for the specified MST instance.

For a given port, the path cost setting can be different for different MST instances to which the port may belong. The switch uses the path cost to determine which ports are the forwarding ports in the instance; that is, which links to use for the active topology of the instance and which ports to block.

The settings are either auto or in a range from 1 to 200,000,000. With the auto setting, the switch calculates the path cost from the link speed:

10 Mbps	2000000
100 Mbps	200000
1 Gbps	20000
Default	Auto

Syntax:

spanning-tree instance <1..4 port-list> priority <priority-multiplier>

Sets the priority for the specified ports in the specified MST instance.

For a given port, the priority setting can be different for different MST instances to which the port may belong. The priority range for a port in a given MST instance is 0 - 255. However, this command specifies the priority as a multiplier (0 - 15) of 16. When you specify a priority multiplier of 0 - 15, the actual priority assigned to the switch is: (priority-multiplier) x 16

Setting priority for a port in a specified MST instance

If you configure 2 as the priority multiplier on a given port in an MST instance, then the actual Priority setting is 32x. After you specify the port priority multiplier in an instance, the switch displays the actual port priority and not the multiplier in the show spanning-tree instance <1..4> or show spanning-tree <port-list> instance <1..4> displays.

You can view the actual multiplier setting for ports in the specified instance by executing show running and looking for an entry in the following format:

spanning-tree instance < 1..4 port-list> priority <priority-multiplier>

For example, configuring port A2 with a priority multiplier of 3 in instance 1, results in this line in the show running output:

Syntax:

spanning-tree <port-list> priority <priority-multiplier>

Sets the priority for the specified ports for the IST (Instance 0) of the region in which the switch resides.

The priority component of the port's Port Identifier is set. The Port Identifier is a unique identifier that helps distinguish this switch's ports from all others. It consists of the priority value with the port number extension—PRIORITY:PORT_NUMBER. A port with a lower value of Port Identifier is more likely to be included in the active topology.

This priority is compared with the priorities of other ports in the IST to determine which port is the root port for the IST instance. The lower the priority value, the higher the priority. The IST root port (or trunk) in a region provides the path to connected regions for the traffic in VLANs assigned to the region's IST instance.

The priority range for a port in a given MST instance is 0 - 240. However, this command specifies the priority as a multiplier (0 - 15) of 16. When you specify a priority multiplier of 0 - 15, the actual priority assigned to the switch is: (priority-multiplier) x 16

Setting priority for specified ports for an IST

Configuring 5 as the priority multiplier on a given port in the IST instance for a region creates an actual priority setting of 80. After specifying the port priority multiplier for the IST instance, the switch displays the actual port priority, not the multiplier, in the show spanning-tree instance ist or show spanning-tree <port-list> instance ist displays. You can view the actual multiplier setting for ports in the IST instance by executing show running and looking for an entry in this format:

spanning-tree <port-list> priority <priority-multiplier>

So configuring port A2 with a priority multiplier of 2 in the IST instance, results in this line in the show running output:

This command enables or disables spanning tree operation for any spanning tree protocol enabled on the switch. Before using to enable spanning tree, ensure that the right version is active on the switch.

Syntax:

Enables or disables spanning tree. Enabling spanning tree with MSTP configured, implements MSTP for all physical ports on the switch according to the VLAN groupings for the IST instance and any other configured instances.

Disabling MSTP removes protection against redundant loops that can significantly slow or halt a network.

This command simply turns spanning tree on or off. It does not change the existing spanning tree configuration.

NOTE: The convergence time for implementing MSTP changes can be disruptive to your network. To minimize such disruption, consider using the spanning-tree pending command (see Enabling an entire MST region at once or exchanging one region configuration for another).

This operation exchanges the currently active MSTP configuration with the currently pending MSTP configuration, making it possible to implement a new MSTP configuration with minimal network disruption or to exchange MSTP configurations for testing or troubleshooting purposes.

When configuring or reconfiguring MSTP, the switch recalculates the corresponding network paths. This can have a ripple effect throughout your network as adjacent MSTP switches recalculate network paths to support the configuration changes invoked in a single switch. Although MSTP employs rapid spanning tree operation, the convergence time for implementing MSTP changes can be disruptive to your network. However, by using the spanning-tree pending feature, you can set up an MSTP on the switch and then invoke all instances of the new configuration at the same time, instead of one at a time.

Syntax:

[no] spanning-tree pending [ apply | <config-name> | <config-revision> | instance | reset ]

Exchanges the currently active MSTP configuration with the current pending MSTP configuration. Options are as follows:

apply	Exchanges the currently active MSTP configuration with the pending MSTP configuration.
<config-name>	Specifies the pending MST region name. Must be the same for all MSTP switches in the region. (Default: The switch's MAC address.)
<config-revision>	Specifies the pending MST region configuration revision number. Must be the same for all MSTP switches in the region. (Default: 0).
	Creates the pending instance and assigns one or more VLANs to the instance.
reset	Copies the switch's currently active MSTP configuration to the pending configuration. This is useful when you want to experiment with the current MSTP configuration while maintaining an unchanged version.

To create a pending MSTP configuration and exchange it with the active MSTP configuration:

1. Configure the VLANs to include in any instances in the new region. When you execute the pending command, all VLANs configured on the switch will be assigned to a single pending IST instance unless assigned to other, pending MST instances. The pending command creates the region's IST instance automatically.

2. Configure MSTP as the spanning tree protocol, then execute write mem and reboot. The pending option is available only with MSTP enabled.

3. Configure the pending region <config-name> to assign to the switch.

4. Configure the pending <config-revision> number for the region name.

5. If you want an MST instance other than the IST instance, configure the instance number and assign the appropriate VLANs (VIDs) using the pending instance <1..4> vlan [ vid | <vid-range> ]

6. Repeat step 5 for each additional MST instance necessary.

7. To review your pending configuration, use the show spanning-tree pending command.

8. To exchange the currently active MSTP configuration with the pending MSTP configuration, use the spanning-tree pending apply command.

The commands in this section apply at the switch (global) level. For configuring spanning tree settings on individual ports, see Configuring MSTP per-port parameters.

Syntax:

Specifies that spanning tree will run in MSTP mode.

Syntax:

Clears spanning tree debug counters.

Resetting the configuration name of the MST region in which a switch resides

Syntax:

Resets the configuration name of the MST region in which the switch resides. This name can include up to 32 nonblank characters and is case-sensitive. On all switches within a given MST region, the configuration names must be identical. For more than one MSTP switch in the same MST region, the identical region name must be configured on all such switches. If the default configuration name is retained on a switch, it cannot exist in the same MST region with another switch.

The default name is a text string using the hexadecimal representation of the switch's MAC address.

The no form of the command overwrites the currently configured name with the default name.

NOTE: This option is available only when the switch is configured for MSTP operation. There is no defined limit on the number of regions you can configure.

Designating the revision number of the MST region for a switch

Syntax:

Configures the revision number designated for the MST region in which you want the switch to reside. This setting must be the same for all switches residing in the same region. Use this setting to differentiate between region configurations in situations such as the following:

• Changing configuration settings within a region where you want to track the configuration versions you use

• Creating a new region from a subset of switches in a current region and want to maintain the same region name.

• Using the pending option to maintain two different configuration options for the same physical region.

This setting must be the same for all MSTP switches in the same MST region.

Range: 0 - 65535

Default: 0

NOTE: This option is available only when the switch is configured for MSTP operation.

Syntax:

spanning-tree force-version [ stp-compatible | rstp-operation | mstp-operation ]

Sets the spanning tree compatibility mode. This command forces the switch to emulate behavior of earlier versions of spanning tree protocol, or return to MSTP behavior. The command is useful in test or debug applications and removes the need to reconfigure the switch for temporary changes in spanning tree operation.

stp-compatible	The switch applies 802.1D STP operation on all ports.
rstp-operation	The switch applies 802.1w operation on all ports except those ports where it detects a system using 802.1D Spanning Tree. RSTP is Rapid Spanning Tree Protocol.
mstp-operation	The switch applies 802.1s MSTP operation on all ports where compatibility with 802.1D or 802.1w spanning tree protocols is not required.

NOTE: Even when mstp-operation is selected, if the switch detects an 802.1D BPDU or an 802.1w BPDU on a port, it communicates with the device linked to that port using STP or RSTP BPDU packets. Also, if errors are encountered as described in Configuring MSTP at a glance, setting force-version to stp-compatible forces the MSTP switch to communicate out all ports using operations that are compatible with IEEE 802.1D STP.

NOTE: When using MSTP rapid state transitions Under some circumstances the rapid state transitions employed by MSTP can increase the rates of frame duplication and misordering in the switched LAN. To allow MSTP switches to support applications and protocols that may be sensitive to frame duplication and misordering, setting the Force Protocol Version (force-version) parameter to stp-compatible allows MSTP to operate with rapid transitions disabled. The value of this parameter applies to all ports on the switch.

Setting the time interval between listening, learning and forwarding states

Hp Procurve Spanning Tree Port Priority

Syntax:

Sets the time the switch waits between transitioning from listening to learning and from learning to forwarding states.

Range: 4 - 30

Default: 15 seconds

Procurve Spanning Tree Priority Boxes

Setting spanning tree to operate in 802. ID legacy mode

Syntax:

Procurve Spanning Tree Priority Code

Forces spanning tree to operate in legacy (802.!D) mode.

Default: MSTP-operation.

The no form of this command returns the switch to the default 802.1s native mode (MSTP-operation)

Syntax:

Setting spanning tree to operate with 802. ID legacy path cost values

Syntax:

Forces spanning tree to operate with legacy (802.!D) path cost values.

Default: 802.1t.

The no form of the command returns the switch to the default 802.1t (not legacy) path cost values.

Specifying the time interval between BPDU transmissions

Syntax:

If MSTP is running and the switch is operating as the CIST (Common and Internal Spanning Tree) root for your network, this command specifies the time in seconds between transmissions of BPDUs for all ports on the switch configured with the Global option (the default). This parameter applies in MSTP, RSTP and STP modes.

During MSTP operation, you can override this global setting on a per-port basis with this command: spanning-tree <port-list> hello-time <1..10>.

Default: 2 seconds.

Syntax:

Resets the number of hops allowed for BPDUs in an MST region. When an MSTP switch receives a BPDU, it decrements the hop-count setting the BPDU carries. If the hop-count reaches zero, the receiving switch drops the BPDU.

The switch does not change the message-age and maximum-age data carried in the BPDU as it moves through the MST region and is propagated to other regions.

Range: 1 - 40 Default: 20

Setting the maximum age of received STP information

Syntax:

Sets the maximum age time for received STP information before it is discarded.

Default: 20 seconds

Syntax:

spanning-tree pending [ apply | <config-revision> | <instance> | reset ]

Manipulates the pending MSTP configuration. The command is useful in test or debug applications and enables rapid reconfiguration of the switch for changes in spanning tree operation.

apply	Applies pending MSTP configuration (swaps active and pending configurations).
<config-name>	Sets the pending MST region configuration name. Default is the switch's MAC address.
<config-revision>	Sets the pending MST region configuration revision number. Default is 0.
<instance>	Change pending MST instance configuration.
reset	Copies the active configuration to pending.

Setting the bridge priority for a region and determining the root switch

Syntax:

Every switch running an instance of MSTP has a Bridge Identifier, which is a unique identifier that helps distinguish this switch from all others. The switch with the lowest Bridge Identifier is elected as the root for the tree.

The Bridge Identifier is composed of a configurable Priority component (2 bytes) and the bridge's MAC address (6 bytes). The ability to change the Priority component provides flexibility in determining which switch will be the root for the tree, regardless of its MAC address.

This command sets the switch (bridge) priority for the designated region in which the switch resides. The switch compares this priority with the priorities of other switches in the same region to determine the root switch for the region. The lower the priority value, the higher the priority. If there is only one switch in the region, then that switch is the root switch for the region.The root bridge in a region provides the path to connected regions for the traffic in VLANs assigned to the region's IST instance. Traffic in VLANs assigned to a numbered STP instance in a given region moves to other regions through the root switch for that instance.

The priority range for an MSTP switch is 0-61440. However, this command specifies the priority as a multiplier (0 - 15) of 4096. That is, when you specify a priority multiplier value of 0 - 15, the actual priority assigned to the switch is: (priority-multiplier) x 4096

For example, with 2 as the priority-multiplier on a given MSTP switch, the Switch Priority setting is 8,192.

NOTE: If multiple switches in the same MST region have the same priority setting, then the switch with the lowest MAC address becomes the root switch for that region.

Syntax:

[no] spanning-tree trap { errant-bpdu | loop-guard | new-root | root-guard }

Enables or disables SNMP traps for errant-BPDU, loop guard, new root and root guard event notifications. This command is designed to be used with the spanning-tree bpdu-filter command (see Configuring BPDU filtering) and the bpdu-protection command (see Enabling and disabling BPDU protection).

errant-bpdu	Enables SNMP notification when an errant BPDU is received. Designed for use with BPDU filtering (see Configuring BPDU filtering).
loop-guard	Enables SNMP notification when a loop guard inconsistency is detected. Designed for use with the Loop Guard option (see STP loop guard).
new-root	Enables SNMP notification when a new root is elected on any VLAN configured for MSTP on the switch.
root-guard	Enables SNMP notification when a root guard inconsistency is detected. See Denying a port the role of root port.

Default for all of the above options: Disabled

The no form of the command disables traps on the switch.