Yealink SIP-T54S Administrator's Manual page 410

Administrator's Guide for SIP-T2 Series/T19(P) E2/T4 Series/T5 Series/CP860/CP920 IP Phones
If it is set to 1 (Enabled), the IP phone will dial the previous dialed out number automatically
when the dialed number is temporarily unavailable.
Web User Interface:
Features->General Information->Auto Redial
Phone User Interface:
Menu->Features->Others->Auto Redial->Auto Redial
auto_redial.interval
Description:
Configures the interval (in seconds) for the IP phone to wait between redials.
The IP phone redials the dialed number at regular intervals till the callee answers the call.
Note: It works only if the value of the parameter "auto_redial.enable" is set to 1 (Enabled).
Web User Interface:
Features->General Information->Auto Redial Interval (1~300s)
Phone User Interface:
Menu->Features->Others->Auto Redial->Redial Interval
auto_redial.times
Description:
Configures the auto redial times when the callee is temporarily unavailable.
The IP phone tries to redial the dialed number as many times as configured till the callee
answers the call.
Note: It works only if the value of the parameter "auto_redial.enable" is set to 1 (Enabled).
Web User Interface:
Features->General Information->Auto Redial Times (1~300)
Phone User Interface:
Menu->Features->Others->Auto Redial->Redial Times
To configure auto redial via web user interface:
Click on Features->General Information.
1.
Select the desired value from the pull-down list of Auto Redial.
2.
Enter the waiting time in the Auto Redial Interval (1~300s) field.
3.
384
Parameters Permitted Values
Integer from 1 to 300
Integer from 1 to 300
Default
10
10