Yealink SIP-T48G Administrator's Manual page 331

Parameters
If it is set to 1 (On), incoming calls to the account X are forwarded to the destination
number when the callee is busy.
X ranges from 1 to 16 (for SIP-T48G/T46G/T29G)
X ranges from 1 to 12 (for SIP-T42G)
X ranges from 1 to 6 (for SIP-T41P/T27P)
X ranges from 1 to 3 (for SIP-T40P/T23P/T23G)
X ranges from 1 to 2 (for SIP-T21(P) E2)
Note: It works only if the value of the parameter "features.fwd_mode" is set to 1
(Custom). It is not applicable to SIP-T19(P) E2 and CP860 IP phones.
Web User Interface:
Features->Forward&DND->Forward->Busy Forward->On/Off
Phone User Interface:
Menu->Features->Call Forward->Busy Forward->Busy Forward
account.X.busy_fwd.target
Description:
Configures the destination number of the busy forward for account X.
X ranges from 1 to 16 (for SIP-T48G/T46G/T29G)
X ranges from 1 to 12 (for SIP-T42G)
X ranges from 1 to 6 (for SIP-T41P/T27P)
X ranges from 1 to 3 (for SIP-T40P/T23P/T23G)
X ranges from 1 to 2 (for SIP-T21(P) E2)
Example:
account.1.busy_fwd.target = 3602
Note: It works only if the value of the parameter "features.fwd_mode" is set to 1
(Custom). It is not applicable to SIP-T19(P) E2 and CP860 IP phones.
Web User Interface:
Features->Forward&DND->Forward->Busy Forward->Target
Phone User Interface:
Menu->Features->Call Forward->Busy Forward->Forward to
account.X.busy_fwd.on_code
Description:
Configures the busy forward on code to activate the server-side busy forward
feature for account X. The IP phone will send the busy forward on code and the
Configuring Basic Features
Permitted Values Default
String within 32
Blank
characters
String within 32
Blank
characters
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