[OpenSER-Users] Avoid Loops between Openser and Asterisk

[Cosimo Fadda]

Hi everybody,
I'm using Opeser as Proxy and one Asterisk as Gateway and Voicemail server.
Suppose that an incoming calls arrives to Ser from Asterisk and the user 
is offline;
Then Openser sends back the Invite to Asterisk that should activate the 
voicemail application but
unfortunately it detects a Loop (482) and rejects the invite.
I think I have to mangle the SIP message in Openser before the send to 
Asterisk again.
This is what I currently do:

if(!lookup("location"))
    {
        #send to voicemail if active but not registerd
        xlog("L_INFO", "Local user offline - M=$rm RURI=$ru F=$fu T=$tu 
IP=$si ID=$ci\n");
        if($avp(s:vmail) == "1")
        {
         route(11);
        }
        else
        {
         route(20);
        }
    }
    else
    {  
       xlog("L_INFO", "Local user online - M=$rm RURI=$ru F=$fu T=$tu 
IP=$si ID=$ci\n");
        route(9);
    }
    exit;

....

route[11]
{
    xlog("L_INFO", "Forwarding request to VM\n");
    prefix("vm");
    sethostport("asterisk-gw:5060");
    #append_branch();
    if (!t_relay())
    {
        xlog("L_INFO", "Unable TO Forward the request to VM\n");
           route(20);
           exit;
    }


What can I do to avoid Loop Detection?

Thanks in advance,

Cosimo Fadda
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