# Setup SIP Switch

Each UI can connect to as many SIP Switch as you want.  These SIP Switches can be running in different servers also.  Each Class 4 switch has a telnet port and this telnet port enable the UI to communicate with it. 

Here is how you need to do to setup the SIP Switch:

![Click on VoIP Gateway on right side](https://4102392624-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-MXPCJcszvw7MAuHjiRr%2F-MdtTGbsq5BTslFhojW9%2F-MdtWTuvXjLYuSEe626Z%2Fimage.png?alt=media\&token=ada6b68e-3916-4ef1-af65-eeb9d3fb3cb9)

 In the VoIP Gateway page, you can specify the telnet IP and port to access to the dnl\_softswitch instance:

![](https://4102392624-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-MXPCJcszvw7MAuHjiRr%2F-MdtTGbsq5BTslFhojW9%2F-MdtWnSlXLj0kuFC8m_W%2Fimage.png?alt=media\&token=1798c718-fe25-4220-bc47-4517f2b340ec)

Each dnlsoftswitch instance can listen to multiple SIP IP:port.  You can click on + to add as many SIP IP:port combination as you need. 

![](https://4102392624-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-MXPCJcszvw7MAuHjiRr%2F-MdtTGbsq5BTslFhojW9%2F-MdtX0KKeJWX8AKrxfUH%2Fimage.png?alt=media\&token=bc0b2a50-d10a-4ac9-a7b8-7002b58f53bb)

After you modify the VoIP gateway, you will need to restart dnl\_softswitch instance in order for the change to take place. 

You can use the following command to check if the SIP port is live or not:

```
[root@ns505183 ~]# netstat -anp |grep 5060
udp        0      0 198.27.82.144:5060      0.0.0.0:*                           27257/dnl_softswitc 
[root@ns505183 ~]# netstat -anp |grep 5080
udp        0      0 198.27.82.144:5080      0.0.0.0:*                           27257/dnl_softswitc 
[root@ns505183 ~]# 
```


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