Configuring Ppp Link Quality Control; Displaying And Debugging Ppp - H3C SecPath Series Operation Manual

Operation Manual – User Access
H3C SecPath Series Security Products

1.2.5 Configuring PPP Link Quality Control

You may use PPP link quality control (LQC) to monitor quality of PPP links. The system
shuts down a link when its quality decreased below the forbidden-percentage and
brings it up when its quality ameliorates exceeding the resumptive-percentage. When
re-enabling the link, PPP LQC experiences a delay to avoid link flapping.
Perform the following configuration in interface view.
Table 1-14 Configure PPP link quality control
Operation
Enable PPP LQC
Disable PPP LQC
By default, the arguments resumptive-percentage and forbidden-percentage are equal.
Note:
Before you enable LQC, the PPP interface sends keepalive packets to the peer
regularly. After you enable LQC on the interface, the PPP interface sends link quality
reports (LQRs) instead for monitoring the link.
When the quality of the link is normal, the system calculates link quality based on each
LQR and shuts down the link if the results of two consecutive calculations are below the
forbidden-percentage. After shutting down the link, the system calculates link quality
every ten L QRs, and brings the link up again if the results of three consecutive
calculations are higher than the resumptive-percentage. That means a disabled link
must experience 30 keepalive periods before it can go up again. If a large keepalive
period is specified, it may take long time for the link to go up.

1.2.6 Displaying and Debugging PPP

When finishing the above configuration, execute display commands in all views to
view running status after the PPP configuration and to verify the effect of the
configuration. And you can debug PPP by executing debugging command in user
view.
Table 1-15 Displaying and debugging
Display the PPP
configuration and status
of a interface
ppp lqc forbidden-percentage [ resumptive-percentage ]
undo ppp lqc
Operation
display interface interface-name
Command
Command
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Chapter 1 PPP Configuration