help • App. D: Internal connections (BRI/PRI) • Installation of a gateway with SX2 DualPRI V2
D.4 Installation of a gateway with SX2 DualPRI V2
In an environment with another PBX (e.g. a fallback SwyxServer), it is possible to forward the exchange connection directly to a PBX if necessary. The SX2 DualPRI V2 has an additional relay, enabling the calls to be forwarded directly even if there is a breakdown.
So long as the relay is activated, i.e. the software (SwyxGate, SwyxServer) is active, the connected PBX is treated as a sub-telecommunication system. If the relay is released, e.g. because
*there is a power failure,
*the service SwyxGate is stopped, e.g. directly by the administrator.
then the connected PBX is linked directly to the external line.
Example:
The SX2 DualPRI V2 is configured so that one part (a controller, equivalent to a PRI) is directly connected in TE mode to the external line and the other part forwards the calls in NT mode to a sub-PBX (e.g. a fallback SwyxServer). If the computer now breaks down, the opening of the relay causes the external line to be connected through directly to the PBX.
Preparation of the SX2 DualPRI V2 before insertion
Before the card is inserted, a jumper is set to establish whether the relay should be used on this card, see .
This is how you check the relay status in the card driver
1 Start the configuration of the driver in computer management (15.2.7 Configuration of the ISDN Card).
2 The relay function must be allowed for one of the two ISDN Controllers.
On the "Advanced" tab, select the entry "ISDN Parameter".
The status of the relay function is indicated in the information field "Standby Information:".
"Standby relay status: enabled / disabled".
* 
If the status is "disabled" for both ISDN controllers, the relay function is deactivated. There will be no through-connection of the external line to the sub-PBX if SwyxWare is disabled.
 
Clocking in the Standby Configuration
In a Standby configuration, one of the ISDN Controllers of SX2 DualPRI V2 is configured in TE mode, the other one in NT mode. The ISDN controller in NT mode must be configured in a way that in the card driver configuration on the „ISDN Parameters" tab the option „Obtain clocking from other board connected via PCM bus" is activated (can be activated in NT mode only!). This ensures that the ISDN controller is synchronous to the ISDN controller in TE mode.