[Asterisk-Users] Re: Failover Device?

[James Harper]

> 
> Matt wrote:
> > On 1/12/06, Tomislav Parcina <tparcina at lama.hr> wrote:
> >> In article
> <c11d02530601110543w56a92b98n5df53ddce0bdbdd at mail.gmail.com>,
> >> mhoppes at gmail.com says...
> >>> First,
> >>> Something seems to be wrong with the list.  I'm not the only
person
> >>> who has expressed seeing their messages either arrive late, or not
at
> >>> all.
> >> I'm sure that I'm not the only person that has notice that there is
> lots
> >> of people that start new thread by replaying to old message. That
way
> >> neither them, or lots of other people, sees that mail as new
therad.
> >
> > Yeah I've noticed that too.. I don't do that though.
> >
> > Ok on to the question at hand.  I am trying to fail over asterisk.
I
> > have PRI redundancy.  What I need, however, is someway to transfer
the
> > PRI from asterisk box A to asterisk box B if asterisk box A fails.
So
> > while, yes, I can build a second asterisk box and use SER, or DNS or
> > whatever to point my sip devices to it... the question is how do I
get
> > the PRIs to know which box to route to?
> 
> How about a relay, driven by something attached to a pin of the serial
> (or parallel) port(s) of one/both servers?
> 

I've been thinking along the same lines. BlackBox in Australia claimed
they could build me a device which would route BRI and PRI lines via
mechanical relays, and could be driven by a very simple heartbeat
failover circuit. But such a device wouldn't be 'A-Tick' certified which
means it would be illegal to connect it to the phone network in
Australia.

I've since been thinking that the best way to accomplish this would
actually be a TDMoE PRI device, which would take the PRI signalling in
one side and send TDMoE out the other. Software heartbeat and failover
would decide which Asterisk box talked to it. You then have the TDMoE
PRI device as the single point of failure, but I believe such a device
has a much longer MTBF than a server, and in any case if you came up
with a relay box (or ISDNGuard for that matter) you would still have
that as the single point of failure anyway.

Can anyone recommend a PRI-to-TDMoE device? Does such a thing exist?

James