Yealink SIP-T2 SERIES Administrator's Manual page 660

Administrator's Guide for SIP-T2 Series/T19(P) E2/T4 Series/CP860 IP Phones
action_url.unhold = http://192.168.0.20/help.xml?IP=$ip
Web User Interface:
Features->Action URL->UnHold
Phone User Interface:
None
action_url.held
Description:
Configures the action URL the IP phone sends when a call is held.
Example:
action_url.held = http://192.168.0.20/help.xml?IP=$ip
Web User Interface:
None
Phone User Interface:
None
action_url.unheld
Description:
Configures the action URL the IP phone sends when a call being held is resumed.
Example:
action_url.unheld = http://192.168.0.20/help.xml?IP=$ip
Web User Interface:
None
Phone User Interface:
None
action_url.mute
Description:
Configures the action URL the IP phone sends when muting a call.
Example:
action_url.mute = http://192.168.0.20/help.xml?IP=$ip
Web User Interface:
Features->Action URL->Mute
638
Parameters Permitted Values
URL within 511 characters
URL within 511 characters
URL within 511 characters
Default
Blank
Blank
Blank