We switched to VOIP : Our old PBX was lacking features, and the prices for phones went sky-high. I purchased an Asterisk EuroISDN card, and some Aastra phones.
Some lessons I learnt the hard way :
A GUI
If you installed a GUI, deinstall it. If you have the GUI config and installation in a backup : remove it from the backup also. Then, print the GUI sources, and shred them. Really, do so. If you have a real problem, and a GUI, and no knowledge of Asterisk, you’re totally screwed.
The hardware
First, make sure Asterisk knows your hardware. dahdi_hardware should give some output. If it doesn’t, reinstall the kernel drivers, and make sure that the driver is loaded. I used the .src.rpm for building those, but the instructions at https://wiki.asterisk.org/wiki/display/AST/Building+and+Installing+DAHDI also work.
Load the kernel drivers : I needed to load wcb4xxp and dahdi.
Asterisk software
I installed Asterisk 10.6, using a homebrew RPM. No special reason for this version : It was the latest available.
Configurating Asterisk
First, I ran dahdi_genconf, that took care of configuring all 4 spans.
My chan_dahdi.conf looks like :
[trunkgroups] [channels] ; Deprecated, don't use it [lines] echocancel = yes echotraining = yes signalling = bri_cpe callerid = asreceived context = bri-incoming group = 1 channel = 1,2 channel = 4,5 dahdichan => 1,2,4,5
The SIP phones also need config. This is done in /etc/asterisk/sip.conf :
[jdioffice](!) type=friend context=sipphones host=dynamic nat=no dtmfmode=auto disallow=all allow=ulaw allow=g722 allow=g729 qualify=yes language=nl [00085D3XXXXX](jdioffice) secret=mysecret
This gives us two asterisk contexts : sipphones, and bri-incoming. You need these to tell Asterisk what to when a call comes in or goes uit on a certain context.
I use a LUA based dialplan : I know how to code, and that gives me an extensions file that is a whole lot better to read then the ‘traditional’ Asterisk dialplan config.
Entrypoints are in a table :
extensions = {
-- Incoming calls
["unauthenticated"] = {
["_."] = e_drop_call
};
["sipphones"] = {
["_#NXX"] = e_hotdesk_login,
["_#000"] = e_hotdesk_logout,
["_0X."] = e_outgoing_sip,
["_NXX"] = e_internal_sip,
["112"] = e_outgoing_emergency,
["911"] = e_outgoing_emergency,
["_*."] = e_dial_custnr,
["_**."] = e_dial_employee
};
["bri-incoming"] = {
["_X."] = e_incoming
};
["default"] = {
include = { "unauthenticated" }
};
}
You can clearly see the context, and the resulting mapping. All names are actual lua functions, which take a context and extension as a result.
Next post : More on the dialplan, things I’ve run into, and the solutions, if available.