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 interface immediately reports the change to the CPU. The CPU then does the following:
Notifies the upper-layer protocol modules (such as routing and forwarding modules) of the change for guiding packet forwarding.
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 physical layer changes only when the suppression interval expires.
To configure physical state change suppression on an Ethernet interface:
Step | Command | Remarks |
|---|---|---|
1. Enter system view. | system-view | N/A |
2. Enter Ethernet interface view. | interface interface-type interface-number | N/A |
3. Set the link-up event suppression interval. | link-delay [msec] delay-time mode up | By default, each time the physical link of a port goes up or comes down, the interface reports the change to the CPU after one second. When this command is configured:
|
4. Set the link-updown event suppression interval. | link-delay [msec] delay-time mode updown | By default, each time the physical link of a port goes up or comes down, the interface reports the change to the CPU after one second. When this command is configured, the link-up or link-down event is not reported to the CPU until the interface is still up or down when the suppression interval (delay-time) expires. |
The link-delay [msec] delay-time mode up command and the link-delay [msec] delay-time mode updown command overwrite each other, and whichever is configured last takes effect.
Do not configure physical state change suppression on a port with RRPP, MSTP, or Smart Link enabled.