[Asterisk-Users] Clustering "NEW THREAD", Almost Working

[JR Richardson]

All,

I made some progress, but it seems the further I go with clustering the
harder things get.  Hmmm, I guess if it were easy, it would be
documented......
 
Anyhow, I have 1 * server as the DUNDi peering master with a ttl=1.  The
only function of this server is to lookup where other sip peers are
registered and forward that info on to the requesting * server.

I have 4 * servers accepting registrations from sip users (phones).  All the
sip phone info is stored in a MySQL database and being accessed through the
realtime engine, and it works great.  A phone registers to a server and the
server checks the database and if an entry is present, the * servers allows
the phone to register and dumps the sip phone into sip show peers, works
great.  I can take the sip entry out of the database and the phone will not
resister in realtime.  Works great.

Now the dial plan setup.  All the extension info is also in the MySQL
database, I have a switch statement in the [siptest] context pointing to the
database for extension logic.  This also works great.  All servers are
pointing to the same data source with all sip extensions in the database
starting with 
exten => 1234,2,Answer and so on
exten => 1235,2,Answer and so on

notice the priority 2 starting point in the database, very important.

This is the good part, in sip.conf, I have regcontext=siptest in the general
section (because it doesn't work in the users section), so when a sip phone
registers on a server, * dynamically inputs an exten => 1234,1,Noop into the
dialplan and immediately the phone is able to be called.  This is working
pretty damn well also.

So at this point I have several phones registered across 4 * servers, all
pulling their info from MySQL, the same data source.  Now let's say phone
1234 and 1235 are registered to server 1 and phone 1236 and 1237 are
registered to server 2, 1234 can call 1235 and vise versa, 1236 can call
1237 and vise versa.

Now from phone 1234 on server 1, I call 1236 on server 2 and because 1236
does not have a priority 1 entry on server 1, the call progresses to a DUNDi
lookup statement in the diaplan logic and request exten 1236 location from
the DUNDi peering master server (these registration servers all are peered
with the dundi peering master server with a ttl=2, so the request will get
past the peering master server and on to the other registration servers).
The request is answered from server 2 and 1234 can now complete a call to
1236. This is great, all is well, life is good, had a big Dallas barbeque
lunch to celebrate because all my sip phones are dynamically registering to
any one of 4 sip registration servers, and the other three servers know who
is registered where through DUNDi lookups.  And it only took me 2 weeks to
get this far.

Now then, let's break it and see what happens, dial any sip phone that is
not actively registered and you get an endless DUNDi lookup request from all
servers except the one you are dialing from.  I only had one other server on
at this time and within seconds produced 590+ IAX trunks initiated back into
a registration server before I could hang up the line.

As far as I can tell, if you make a call from server 1, exten 1234 to exten
1236, but 1236 is not actively registered on any other server, the other
server will get the DUNDi lookup request and not know where the phone is so
it keeps looking up and calling itself to find an extension that is not
there, or something, anyhow it's a bad thing.

Now intrinsically knowing that this protocol is smarter than me, I'm
guessing that I have incorrect dialplan logic that is allowing this to
happen.  I'm wondering how I can set up a dialplan flow that will do this:

>From Server 1, pick up phone and dial a number (phone)(exten), 
1. * checks to see if the phone is first registered and on-line on server 1
2. if so, dial it, follow standard dialplan login
3. if not, goto DUNDi switch, lookup where it may be
(this is pretty much working good)

On Server 2,
1. DUNDi lookup request comes in
2. check to see if extention is active on this server(2), if not, stop, or
at least don't continue to look for something within your own dialplan that
is not there.

I'm very open to suggestions.  I feel like I'm so close but also still far
away.

Thanks

JR