HP HSR6800 Configuration Manual page 17

Figure 2 Single-port loopback
Figure 3 Multi-port loopback
You can enable loopback detection to detect loops on an interface and, if the interface supports the
loopback-detection action command, configure the protective action to take on the receiving interface
when a loop is detected, for example, to shut down the interface. Depending on whether a protective
action is configured, the device takes the actions in
Table 1 Actions to take upon detection of a loop condition
Port type
Access port
Hybrid or trunk
port
Configuration restrictions and guidelines
To use loopback detection on an Ethernet interface, you must enable the function both globally and
•
on the interface.
To disable loopback detection on all interfaces, run the undo loopback-detection enable command
•
in system view.
Actions
No protective action is configured
•
Place the receiving interface in controlled
mode. The interface discards all incoming
packets, but still forwards outgoing packets.
•
Generate traps.
•
Delete all MAC address entries of the
interface.
•
Generate traps.
•
If loopback detection control is enabled,
place the receiving interface in controlled
mode. The interface discards all incoming
packets, but still forwards outgoing packets.
•
Delete all MAC address entries of the
interface.
Table 1 to alleviate the impact of the loop condition.
A protective action is configured
•
•
•
•
•
•
12
Perform the configured protective
action.
Generate traps and log messages.
Delete all MAC address entries of the
interface.
Create traps and log messages.
If loopback detection control is
enabled, take the configured
protective action on the interface.
Delete all MAC address entries of the
interface.