In this section:

EdgeMarc models 4806, 4808, and 6000 may be configured with a PRI that provides support for a legacy PBX.

When the EdgeMarc is in local mode, this PRI acts in one of the two ways:

  1. The EdgeMarc can route calls from the PBX to an FXO for emergency outbound calling. By default, calls are received on an FXO port and forwarded to the PRI. The following pages contain information on configuring the FXO section of the EdgeMarc:

              Configuring the SIP Gateway

              Configuring Global SIP Gateway FXO/Line Port Settings

              Configuring SIP Gateway FXO Ports

        2. Alternatively, the EdgeMarc can shut down the PRI thus signaling to the PBX that an alternate route may be used. If this behavior is desired, complete the steps below.

This requires VOS version 15.8.4 or later to function properly.

In VOS version 15.8.4, this requires the EdgeMarc to be licensed for survivability. As of VOS version 16.3, the survivability license is optional.

Configuring the PRI to follow the call control state of the EdgeMarc

 The ENABLE_PRI_DCHAN_SURV flag in the file /etc/config/sipua_pri_defs.conf controls how the PRI state follows the call control state of the EdgeMarc. Possible values are off and on, with off being the default setting. If the parameter is not present in the file, the setting is set to off. In the “off” state, the PRI D channel will remain up regardless of whether the EdgeMarc is in local or remote call control mode.

To change the behavior of the EdgeMarc such that the PRI goes down when the EdgeMarc enters local mode, set the value to “on” by completing the following steps:

1. Open an SSH session to the EdgeMarc.

2. Change to directories to the configuration directory:

cd /etc/config

3. Display the file sipua_pri_defs.conf:

cat sipua_pri_defs.conf

4. Check the file to see if a line PRI_DCHAN_SURV is present and note the value.
5. 
If the line is not present, then run the command:

echo “ENABLE_PRI_CHAN_SURV=on” >> sipua_pri_defs.conf

6. Save the changes:

cfg_commit

7. Restart the UA services for the change to take effect. Note this will disrupt active calls:

killall ewua

8. If parameter is already configured but not set to the desired value, then copy the contents of sipua_pri_defs.conf to a text editor, set the value, and replace the new contents on the EdgeMarc. Then save and restart the UA per the above steps.

The state of the PRI now follows the state of the active SIP server as determined by its response to SIP Options messages. If responses to SIP Options are not received, the PRI is taken out of service.

SIP Options Passthrough

The Edgemarc now supports having the PRI D-channel correspond with whether the Edgemarc is receiving SIP Options messages from the configured SIP servers.

To enable this feature, the Enable keepalives from active server box must be checked on the survivability page:

When this box is selected, the Edgemarc is able to receive and respond to SIP Options messages, and the PRI will be brought into service.