2
By default, an Ethernet interface is up.
Configuring jumbo frame support
About this task
Jumbo frames are frames larger than 1600 bytes and are typically received by an Ethernet interface
during high-throughput data exchanges, such as file transfers.
The Ethernet interface processes jumbo frames in the following ways:
•
When the Ethernet interface is configured to deny jumbo frames (by using the
undo
jumboframe enable
command), the Ethernet interface discards jumbo frames.
•
When the Ethernet interface is configured with jumbo frame support, the Ethernet interface
performs the following operations:
Processes jumbo frames within the specified length.
Discards jumbo frames that exceed the specified length.
Procedure
1.
Enter system view.
system-view
2.
Enter Ethernet interface view.
interface interface-type interface-number
3.
Configure jumbo frame support.
jumboframe enable
[
size
]
By default, the device allows jumbo frames within 1600 bytes to pass through.
If you set the
size
argument multiple times, the most recent configuration takes effect.
Configuring dampening on an Ethernet interface
About this task
The interface dampening feature uses an exponential decay mechanism to prevent excessive
interface flapping events from adversely affecting routing protocols and routing tables in the network.
Suppressing interface state change events protects the system resources.
If an interface is not dampened, its state changes are reported. For each state change, the system
also generates an SNMP trap and log message.
After a flapping interface is dampened, it does not report its state changes to the CPU. For state
change events, the interface only generates SNMP trap and log messages.
Parameters
•
Penalty
—The interface has an initial penalty of 0. When the interface flaps, the penalty
increases by 1000 for each down event until the ceiling is reached. It does not increase for up
events. When the interface stops flapping, the penalty decreases by half each time the half-life
timer expires until the penalty drops to the reuse threshold.
•
Ceiling
—The penalty stops increasing when it reaches the ceiling.
•
Suppress-limit
—The accumulated penalty that triggers the device to dampen the interface. In
dampened state, the interface does not report its state changes to the CPU. For state change
events, the interface only generates SNMP traps and log messages.
•
Reuse-limit
—When the accumulated penalty decreases to this reuse threshold, the interface is
not dampened. Interface state changes are reported to the upper layers. For each state change,
the system also generates an SNMP trap and log message.
