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To check if the configuration worked, go to "stateState" under "management Management +":

Dialplan configuration

Finally, in order to make calls via the SIM card, create dialplan Dialplan rules under "Dialplan". To know how it works, check here. 

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• One GSM group of port per SIM card
• One SIP account between the gateway and the IPBX per SIM card. As each SIP account will have the same IP address, you should choose the "to user" match type in order for the gateway to make the difference between each account and to route the call to the right SIM card.
  
• Two dialplan Dialplan rules per SIM card (from the IPBX to the gateway and the other way around).

The aim of such a configuration is to enable the IPBX to route the call to the SIM card it chooses by sending it to a certain SIP trunk connected to only 1 SIM card. If only one SIP trunk is created, the gateway chooses where to send the call. The dialplan Dialplan configuration of the gateway is then more complicated. 

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In this configuration, it is the Gateway gateway which chooses to which SIM card the call should be routed to. Specifications in the dialplan Dialplan will need to be made in the "Destination" field in order to route the call to the right SIM card.

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