HP VPN Firewall Appliances Network Management Configuration Guide

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By default, the packet format recognition mode of a port is auto. The port automatically distinguishes the
two MSTP packet formats, and determines the format of packets that it will send based on the recognized
format.
You can configure the MSTP packet format on a port. When operating in MSTP mode after the
configuration, the port sends and receives only MSTP packets of the format that you have configured to
communicate with devices that send packets of the same format.
MSTP provides MSTP packet format incompatibility guard. In MSTP mode, if a port is configured to
recognize/send MSTP packets in a mode other than auto, and if it receives a packet in a format different
from the specified type, the port becomes a designated port and remains in the discarding state to
prevent the occurrence of a loop.
MSTP provides MSTP packet format frequent change guard. If a port receives MSTP packets of different
formats frequently, the MSTP packet format configuration contains errors. If the port is operating in MSTP
mode, it will be shut down for protection. Ports disabled in this way can be re-activated after a detection
interval. For more information about the detection interval, see Getting Started Guide.
To configure the MSTP packet format to be supported on a port:
Ste
p
Command Remarks
1. Enter system view.
system-view N/A
2. Enter Ethernet interface view or Layer 2
aggregate interface view.
interface interface-type
interface-number
N/A
3. Configure the mode that the port uses to
recognize/send MSTP packets.
stp compliance { auto |
dot1s | legacy }
The default setting is auto.
Enabling the spanning tree feature
You must enable the spanning tree feature for the device before any other spanning tree related
configurations can take effect. You can disable the spanning tree feature for certain ports with the undo
stp enable command to exclude them from spanning tree calculation and save CPU resources of the
device.
In STP, RSTP, or MSTP mode, make sure the spanning tree feature is enabled globally and on the desired
ports.
To enable the spanning tree feature in STP, RSTP, or MSTP mode:
Ste
p
Command Remarks
1. Enter system view.
system-view N/A
2. Enable the spanning tree
feature globally.
stp enable
By default, the spanning tree
feature is disabled globally.
3. Enter Ethernet interface
view or Layer 2 aggregate
interface view.
interface interface-type
interface-number
N/A
4. Enable the spanning tree
feature for the port.
stp enable
Optional.
By default, the spanning tree
feature is enabled on all ports.