Command Reference Guide

3Com Router 5000 Family and Router 6000 Family ppp lqc ● 257
Command Reference
ppp lqc
Purpose Use the ppp lqc command to enable PPP link quality control (LQC).
Use the undo ppp lqc command to disable PPP link quality control.
Syntax ppp lqc forbidden-percentage [ resumptive-percentage ]
undo ppp lqc
Parameters forbidden-percentage
Link quality percentage threshold. Once the quality of
a link decreased below this percentage, the link is
taken down. Valid values are 0 to 100.
resumptive-percentage
Link quality percentage threshold. The link that has
been taken down is brought up again once its quality
exceeds this percentage. Valid values are 0 to 100.
Default By default, PPP LQC is disabled.
By default, the arguments resumptive-percentage and
forbidden-percentage are equal.
Example Enable LQC on interface Serial 0/0/0, setting forbidden-percentage to 90% and
resumptive-percentage to 95%.
[Router-Serial0/0/0] ppp lqc 90 95
View This command can be used in the following views:
■ Interface view
Description You may use PPP LQC to monitor quality of PPP links including those in MP bundles.
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.
Note that the value of resumptive-percentage must be equal to or greater
than that of
forbidden-percentage.
When enabling LQC at both ends of a PPP link, you must use the same parameter
settings on the routers at both ends. Normally, you are not encouraged to enable LQC
at both ends of a link.
Besides, you are not encouraged to enable PPP LQC on a dial-up line. That is
because in case the link is disabled, the DCC would disconnect the dial-up line,