On multiline IP phones, lifting the handset automatically selects the first ringing line on the phone or, if no line is ringing, selects the first available idle line for outgoing calls. This is the default behavior for all multiline IP phones.
It may be desired that a particular line be selected whenever an outgoing line is made.
ephone 34
auto-line 3 answer-incoming
•auto-line—Picking up the handset answers the first ringing line or, if no line is ringing, selects the first idle line. This is the default.
•auto-line button-number—Picking up the handset for an outgoing call selects the line associated with the specified button. The default if this argument is not used is the topmost available line.
•auto-line button-number answer-incoming—Picking up the handset answers the incoming call on the line associated with the specified button.
•auto-line incoming—Picking up the handset answers the first ringing line but, if no line is ringing, does not select an idle line for an outgoing call. Pressing a line button selects a line for an outgoing call.
•no auto-line—Disables automatic line selection. Pressing the Answer soft key answers the first ringing line, and pressing a line button selects a line for an outgoing call. Picking up the handset does not answer calls or provide dial tone.
Reference: CME Admin Guide
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