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Documentation: How do I debug FreeSentral?

This tutorial tries to give you some help in the unfortunate situation your network is not working correctly.

Try your network connection by making a call. This will work only if you followed the steps presented in How to set up office branches in headquarter. If you still think you did a proper set up of the branches, take a look at the information below:


This part isn't that great but somebody has to do it. Yes, it's the finding and fixing errors part.

On this page... (hide)

  1. 1. Advices
  2. 2. Telnet
  3. 3. The SIP module

1.  Advices

Here are some advices to take into consideration:

Be sure to double-check your network settings, before jumping to telnet and command line typing. Look carefully if you added the ranges correctly, if you typed the appropriate IP host and extension for each VoIP phone. If you checked an advanced option without ensuring it is the right one, the connection won't work.

The “Trusted” setting is very important when routing calls from outside the network or from other branches. The headquarter routes external calls from an added gateway(branch) to another added gateway(branch or provider) only if “Trusted” is enabled. You will create a security issue if you check this setting for the provider.

The extension of the caller will not be seen by the called if “Send extension” is unchecked. Instead of the caller's extension, the System Caller ID of the headquarter will be visible. Also when adding a dial plan don't forget to step through the cutting of digits part. If you miss to cut the prefix, in some cases, the routing of the call may be impossible.

2.  Telnet

Only after starting Yate on every host you may use telnet to see how your network is interacting during a call. Type the following commands in the command line:

 telnet 5038                       
 debug freesentral on   

Tips: You should modify the localhost's IP or the port used according to the specific situation. 5038 is the default port for Yate.

The output of these commands can be seen in the headquarters' telnet. Observe the steps above discussed in this command line capture.

 [cristina@localhost ~]$ telnet 5038
 Connected to localhost (          
 Escape character is '^]'.                    
 YATE 3.0.0-alpha1 ( ready.

 debug on
 Debug level: 8 local: on
 debug freesentral on    
 Enabling debug on FreeSentral routing

When installing FreeSentral, be careful which path you selected for FreeSentral scripts and configuration files to go to in Yate directories. Be sure to add the required files for a correct interaction between applications. To verify that see the step below:


Tips: After connecting to telnet, type the “external” command. This will show the scripts you have in your Yate.

If you don't have register.php, calls can't be made inside or outside the branch.

3.  The SIP module

Start telnet as described above and type the “debug on” command if you plan to monitor your SIP module. This command is used for showing the SIP module output right in the telnet terminal. After this step, you want to rise your level on SIP debugging. “Debug sip level 10” does just that.

 debug on
 Debug level: 5 local: on
 debug level 10
 Debug level: 10 local: on
 debug sip on
 Module sip debug on level 5
 debug sip level 10
 Module sip debug on level 10

Now you just have to read the information listed below after you used the commands aboves. It will look like this:

 <sip:INFO> Sending 'REGISTER' 0x119c060 to 
 Contact: <sip:091@> 
 Expires: 600 
 To: <> 
 Via: SIP/2.0/UDP;rport;branch=z9hG4bK475697057 
 From: <>;tag=651666173 
 User-Agent: YATE/3.0.0 
 Max-Forwards: 70 
 Content-Length: 0 
 <sip:CALL> SIP line 'provider' logon success to


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Page last modified on February 23, 2012, at 01:05 AM