[asterisk-users] Looking for PRI Card with automatic fail over

[Technical Support]

On 8/4/2015 3:47 AM, A J Stiles wrote:
> On Monday 03 Aug 2015, Eric Klein wrote:
>> Hi all,
>>
>> Strange request, I have a customer where we are putting an Asterisk PBX in
>> front of a legacy (non-VoIP) PBX. One of the requirements it that the
>> Asterisk PBX have 2 PRI ports (on towards the legacy PBX and one towards
>> the carrier) with the ability to go to pass through should the Asterisk PBX
>> (software or hardware level) fail.
>>
>> I did not see this feature in the Digium, Sangoma, Allo, or OpenVox cards.
>>
>> Does anyone know of a card that will do this? I know that Digium has an
>> external box (the r850) that does something similar for 2 PBXs making them
>> high availability, but in this case I only have the 1 Asterisk box acting
>> as a gateway and passing some calls out over SIP and IAX2.
>>
>> Any suggestions would be appreciated.
> Use a 4-pole change-over relay to switch the PRI connection either to the
> Asterisk box if it gets some sort of "heartbeat" signal from the computer
> (say, toggling one of the lines of a printer port, if the motherboard still
> has one),  or the old PABX?
>
> You might have to do some mean, down and dirty low-level programming, to embed
> your heartbeat-generating code in Asterisk's idle loop; but the Source Code is
> out there, if you fancy the challenge .....
>
Building on the answer above, have a look at ESL labs - who make such a 
relay that can bypass the PRI to the Asterisk server.  As well, have a 
look at HAAst (www.telium.ca) which can monitor Asterisk and then 
control the ESL relay to bypass Asterisk in case of failure.

-Raj-

P.S. My opinions do not necessarily reflect those of my employer. As I 
am employed by Telium you can bet that me opinions are biased!