24 Jan
2017
24 Jan
'17
11:25 a.m.
I'm following the latest Kamailio and Asterisk Realtime guide to offload
registrations from my FreePBX / Asterisk setup and possibly load balance
down the road. I'm running Kamailio 4.4.5 and Asterisk 11.6-cert15. I
realize FreePBX isn't realtime and will work around that with a database
view, etc.
I was excited to see Kamailio will handle multiple devices registering to
the same device/extension and placing / receiving calls works. I did run
into an issue when any device unregisters Kamailio always forwards the
register with expires 0 to Asterisk. To workaround this I modified the
route[REGFWD] and added the if($hdr(Expires)==$null) chunk of code. I
wanted to use caller->count, but ran into stale contact records with
expires set to deleted. I then tried enumerating the contacts, but don't
understand why ulc(caller->expires) is 10 when kamctl ul show shows expires
deleted. The code below works, but I was hoping for an explanation of the
expires = 10 or if there was a better way to handle this scenario.
Additionally I enabled presence (WITH_PRESENCE) but Kamailio responds 489
bad event for subscribe requests from devices registered to it. I was
hoping it would proxy these to Asterisk for BLF support. If somebody could
point me in the right direction it would be appreciated.
# Forward REGISTER to Asterisk
route[REGFWD] {
if(!is_method("REGISTER"))
{
return;
}
if($hdr(Expires)==$null)
{
reg_fetch_contacts("location", "$sel(contact.uri)",
"caller");
$var(i) = 0;
$var(j) = 0;
while($var(i) < $(ulc(caller=>count)))
{
if($(ulc(caller=>expires)[$var(i)])!=10)
{
$var(j) = $var(j) + 1;
}
$var(i) = $var(i) + 1;
}
if($var(j)>=1)
{
return;
}
}
$var(rip) = $sel(cfg_get.asterisk.bindip);
$uac_req(method)="REGISTER";
$uac_req(ruri)="sip:" + $var(rip) + ":" +
$sel(cfg_get.asterisk.bindport);
$uac_req(furi)="sip:" + $au + "@" + $var(rip);
$uac_req(turi)="sip:" + $au + "@" + $var(rip);
$uac_req(hdrs)="Contact: <sip:" + $au + "@"
+ $sel(cfg_get.kamailio.bindip)
+ ":" + $sel(cfg_get.kamailio.bindport) +
">\r\n";
if($sel(contact.expires) != $null)
$uac_req(hdrs)= $uac_req(hdrs) + "Expires: " +
$sel(contact.expires) + "\r\n";
else
$uac_req(hdrs)= $uac_req(hdrs) + "Expires: " +
$hdr(Expires) + "\r\n";
uac_req_send();
}
Thanks,
Ryan