H3C Technologies H3C S12500 Series Switches - Manual (Page 80)

67
Implementation of MSTP on devices
MSTP is compatible with STP and RSTP. STP and RSTP protocol packets can be recognized by devices
running MSTP and used for spanning tree calculation.
In addition to basic MSTP functions, the following functions are provided for ease of management:
• Root bridge hold
• Root bridge backup
• Root guard
• BPDU guard
• Loop guard
• TC-BPDU guard
• Support for hot swapping of interface cards and active/standby changeover.
Protocols and standards
• IEEE 802.1d: Media Access Control (MAC) Bridges
• IEEE 802.1w: Part 3: Media Access Control (MAC) Bridges—Amendment 2: Rapid Reconfiguration
• IEEE 802.1s: Virtual Bridged Local Area Networks—Amendment 3: Multiple Spanning Trees
Spanning tree configuration task lists
Configuration restrictions and guidelines
• Before configuring a spanning tree, you must determine the spanning tree protocol to be used (STP,
RSTP, PVST, or MSTP) and plan the device roles (the root bridge or leaf node).
• If GVRP and a spanning tree protocol are enabled on a device at the same time, GVRP packets are
forwarded along the CIST. To advertise a certain VLAN within the network through GVRP, make
sure this VLAN is mapped to the CIST when you configure the VLAN-to-instance mapping table. For
more information about GVRP, see "Configuring GVRP."
• The spanning tree configurations are mutually exclusive with any of the following functions on a port:
RRPP, Smart Link, and BPDU tunnel.
• The spanning tree configurations made in system view take effect globally. Configurations made in
Ethernet interface view take effect on the current interface only. Configurations made in port group
view take effect on all member ports in the port group. Configurations made in Layer 2 aggregate
interface view take effect only on the aggregate interface. Configurations made on an aggregation
member port can take effect only after the port is removed from the aggregation group.
• After you enable a spanning tree protocol on a Layer 2 aggregate interface, the system performs
spanning tree calculation on the Layer 2 aggregate interface but not on the aggregation member
ports. The spanning tree protocol enable state and forwarding state of each selected member port
is consistent with those of the corresponding Layer 2 aggregate interface.
• Though the member ports of an aggregation group do not participate in spanning tree calculation,
the ports still reserve its spanning tree configurations for participating spanning tree calculation
after leaving the aggregation group.