[Asterisk-Users] high availibilty (heartbeats) - a good way to ensure automatic redundency?

[David John Walsh]

being from a telecoms background, the thought of a single asterisk box
solution (even in a low production environment of say <10 phones)
worries me slightly!

starting from say a base of asterisk at home, you would have several
MySQL databases, in addition to numerous config files.

I have looked at high availiblity solutions, and from a hardware
monitoring point of view, its relitivly straight forward, you have 2
(identical?) boxes, each with 2 network interfaces.  One of the
network interface cards on each box has the same IP address, there is
another cable that is sending a heartbeat message between the two
boxes, heart beat fails the other box brings up automatically the
interface.

I have used HA on firewalls, and as the equipment is propriertary you
talk to the master side, which pushes config and state to the slave,
in the same way telephone exchanges run 1 micro-instruction behind the
other.  Obviously howver if you have a PRI on the box, it will lose
its calls, IP could be more resilient.

asterisk as it stands isn't geared up for this push of state, so
leaving that to one side there are a few obvious questions, but
firstly my assumptions.

MySQL has some sort of master/slave database system built in, so that
config is ok.  AMP self generates the dynamic config, so a cron job to
reload the slave every few minuites is possible to keep that part in
sync

to my questions (sorry its dragged slightly).  How can the astdb (the
one that you type show database at the asterisk cli) be kept in sync??

is this the right way to design a warm standby system or is there an
already established method.

The wiki suggests HA, but doesn't specify how.  Googling doesn't seem
to find anything (I have been trying on and off for a couple of days
now)


Thanks for any comments