H3C Technologies H3C S12500 Series Switches - Manual (Page 18)

10
Configuring physical state change suppression on an Ethernet
interface
The physical link state of an Ethernet interface is either up or down. Each time the physical link of a port
goes up or comes down, the system immediately reports the change to the upper-layer protocol modules
(such as routing and forwarding modules) for packet transmission, and automatically generates traps
and logs, informing the user to take corresponding actions.
To prevent frequent physical link flapping from affecting system performance, configure physical state
change suppression to suppress the reporting of physical link state changes. The system reports a
physical layer change unless the physical layer state change is not recovered when the suppression
interval expires. If you want to obtain physical layer changes within the suppression interval, enable the
damping function with the link-delay enable trap updown command on the port. When the link-delay
enable trap updown command is configured on an interface, the interface does not report link layer state
changes to upper layer modules, but it generates traps and logs to inform the user to take corresponding
actions.
To configure physical state change suppression on an Ethernet interface:
Step Command Remarks
35. Enter system view. system-view N/A
36. Enter Ethernet interface view. interface interface-type
interface-number
N/A
37. Configure the physical state
change suppression interval. link-delay delay-time
By default, the physical state
change suppression interval on an
Ethernet interface is 1 second.
When the link-delay delay-time
command is configured, the
link-down or link-up event is not
reported to the CPU unless the
interface is still down or up when
the suppression interval
(delay-time) expires.
38. Configure the link-up event
suppression interval.
link-delay delay-time mode up
By default, the physical state
change suppression interval on an
Ethernet interface is 1 second.
When the link-delay delay-time
mode up command is configured:
• The link-up event is not reported
to the CPU unless the interface
is still up when the suppression
interval (delay-time) expires.
• The link-down event is
immediately reported.
39. Enable the damping function
on the port.
link-delay enable trap updown
Optional.
By default, the damping function is
disabled on a port.