Here are the steps to set date and time in linux
Different IP Phones require different methods of provisioning. Below I describe how to do this on Grandstream phones (tested on GXP285) with firmware: 220.127.116.11
Here is a sample on running a service to startup in centos:
Hotline/Warmline, also known as Private Line Automatic Ringdown (PLAR), is a line used for priority telephone service. When using with a SIP phone you must make sure the phone supports this feature. As of this writing I know that Polycom SIP phones support sending a signal to Asterisk upon the offhook event.
Below is a simple and intuitive dialplan by which you can add the phone lock feature to your Asterisk system. Take note that the provided dialplan only locks the phone from calling out to PSTN.
The Cisco ATA 18X series can run either SCCP, H323 or SIP voice protocols making it very flexible.
Another note of importance is that they do not support two ports running the G.729 codec simultaneously. If one port is using G.729, the other will use G.711. In this manual we are using a SIP firmware (ata_03_02_04_sccp_090202_a). If you want to update to other firmwares or perhaps protocols, I suggest you read the last 2 links provided in the resources section.
In order to add Persian language we need to do some modifications on the Asterisk source code. For that, download the same Asterisk version as your current one (in case you’re using FreePBX/Trixbox). The main thing to change is the Asterisk say digits. Here is what must be changed: