It looks like that command is for FXO ports. I have a fax server plugged into a four port fxs/did fard.
Here is the information on the command:
supervisory disconnect dualtone voice-class
To assign a previously configured voice class for Foreign Exchange Office (FXO) supervisory disconnect tone to a voice port, use the supervisory disconnect dualtone voice-class command in voice port configuration mode. To remove a voice class from a voice-port, use the no form of this command.
supervisory disconnect dualtone {mid-call | pre-connect} voice-class tag
no supervisory disconnect dualtone voice-class tag
Syntax Description
mid-call
Configures tone detection to operate throughout the duration of the call.
pre-connect
Configures tone detection to operate during call setup and to stop when the called telephone goes off-hook.
tag
A unique identification number assigned to one voice class. The tag number maps to the tag number assigned using the voice class dualtone global configuration command. The range is from 1 to 10,000.
Defaults
No voice class is assigned to a voice port.
Command Modes
Voice-port configuration
Command History
Release Modification
12.1(3)T
This command was introduced on the Cisco 2600, 3600, and MC3810 series.
Usage Guidelines
You can apply an FXO supervisory disconnect tone voice class to multiple voice ports. You can assign only one FXO supervisory disconnect tone voice class to a voice port. If a second voice class is assigned to a voice port, the second voice class replaces the one previously assigned. You cannot assign separate FXO supervisory disconnect tone commands directly to the voice port.
This feature is applicable to analog FXO voice ports with loop-start signaling.
Examples
The following example assigns voice class 70 to FXO voice port 1/5 of a Cisco MC3810 series concentrator and specifies tone detection during the entire call duration:
voice-port 1/5
no echo-cancel enable
supervisory disconnect dualtone mid-call voice-class 70
The following example assigns voice class 80 to FXO voice port 0/1/1 of a Cisco 3600 series router and specifies tone detection only during call setup:
voice-port 0/1/1
no echo-cancel enable
supervisory disconnect dualtone pre-connect voice-class 80
Related Commands
Command Description
channel-group
Defines the time slots of each T1 or E1 circuit.
mode
Sets the mode of the T1/E1 controller and enters specific configuration commands for each mode type in VoATM.
voice class dualtone
Creates a voice class for FXO tone detection parameters.
