HP manual 209

Item	Description
	Sets the priority and path cost of the port in the current MSTI:
	• Priority—The priority of a port is an important factor in determining whether the port
Instance	can be elected as the root port of a device. If all other conditions are the same, the
	port with the highest priority will be elected as the root port. On an MSTP-enabled
(Instance ID,	device, a port can have different priorities in different MSTIs, and the same port can
Port Priority,	play different roles in different MSTIs, so that data of different VLANs can be
Auto Path	propagated along different physical paths, implementing per-VLAN load balancing.
Cost, and	You can set port priority values based on the actual networking requirements.
Manual Path	• Path cost—A parameter related to the rate of a port. On an MSTP-enabled device, a
Cost)	port can have different path costs in different MSTIs. Setting appropriate path costs
	allows VLAN traffic flows to be forwarded along different physical links, achieving
	VLAN-based load balancing. The device can automatically calculate the default
	path cost. Alternatively, you can also manually configure path cost for ports.
	• Point to Point
	SpecifIes whether the port is connected to a point-to-point link:
	{ Auto—Configures the device to automatically detect whether or not the link type
	of the port is point-to-point.
	{ Force False—The link type for the port is not point-to-point link.
	{ Force True—The link type for the port is point-to-point link.
	If a port is configured as connecting to a point-to-point link, the setting takes effect on the
	port in all MSTIs. If the physical link to which the port connects is not a point-to-point link
	and you force it to be a point-to-point link by configuration, the configuration might incur
Advanced	a temporary loop.
	• Transmit Limit—Configures the maximum number of MSTP packets that can be sent
	during each Hello interval.
	The larger the transmit limit is, the more network resources will be occupied. HP
	recommends that you use the default value.
	• MSTP Mode—Sets whether the port migrates to the MSTP mode.
	In a switched network, if a port on an MSTP (or RSTP) device connects to a device
	running STP, this port will automatically migrate to the STP-compatible mode. After
	the device running STP is removed, the port on the MSTP (or RSTP) device might not
	be able to migrate automatically to the MSTP (or RSTP) mode, but will remain
	operating in the STP-compatible mode. You can set this option to enable the port to
	automatically migrate to the MSTP (or RSTP) mode.
	Selects one or multiple ports on which you want to configure MSTP on the chassis front
Select port(s)	panel. If aggregate interfaces are configured on the device, the page displays a list of
	aggregate interfaces below the chassis front panel. You can select aggregate interfaces
	from this list.

Table 61 Protection types

Protection type	Description
	Sets the port as an edge port.
	Some ports of access layer devices are directly connected to PCs or file servers,
	which cannot generate BPDUs. You can set these ports as edge ports to achieve
Edged Port	fast transition for these ports.
	HP recommends that you enable the BPDU guard function in conjunction with the
	edged port function to avoid network topology changes when the edge ports
	receive configuration BPDUs.
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