[Freeswitch-users] High Availability Cluster Module for FreeSWITCH

[Anthony Minessale]

I believe some more planning and thought needs to go into this before
proceeding with code.
I recommend a continued discussion.  My point of view is we should
specifically review the way FS does the message exchange since its the
cornerstone of many other possible cluster scenarios besides
just fault tolerance.  Some are starting to build this externally and I
think the real answer is a more clean abstraction between the framework for
many FS communicating with each other and the business logic.  So some of
what people like plivo and 2600hz do externally would be better served as
part of FS at the comms level and then still separate the logic.  That way
everyone can benefit from the low level code.




On Mon, Feb 11, 2013 at 12:37 PM, Henry Huang <red.rain.seven at gmail.com>wrote:

> I would choose to go with Elliot's idea of having the HA being build
> within the FS itself under the condition that it's a easy adaptation
> comparing to having to use and struggling with Pacemaker and Corosync. They
> can literally take months if someone is starting from scratch.
>
> And it would be nice to have this kind of capability to go against those
> brand name solutions.
>
>
> On Mon, Feb 11, 2013 at 6:06 AM, Eliot Gable <egable+freeswitch at gmail.com>wrote:
>
>> On Mon, Feb 11, 2013 at 7:36 AM, Marcin Gozdalik <gozdal at gmail.com>wrote:
>>
>>> +1
>>>
>>> I do not doubt mod_ha is necessary inside of FS  and it may be
>>> better/simpler than writing Pacemaker resource agent, but writing
>>> yet-another-cluster-communication-engine is IMHO the wrong way to go
>>> and using Corosync for communication will give a lot of value from
>>> mature codebase.
>>>
>>>
>> I understand what you are saying, but what I am trying to get across is
>> that I am not writing yet-another-cluster-communication-engine. All I am
>> really doing is combining a multicast messaging API written by Tony and the
>> event API in FS to broadcast existing state information between multiple FS
>> nodes, as well as adding a tiny amount of logic on top of that to
>> coordinate call fail over and recovery. That's probably a little
>> over-simplified, but it gets the point across. The network communication
>> code is already in FS and well tested. The event system is already in FS
>> and well tested. I have already written the code to the point that it
>> parses the configuration files and starts sending heartbeats out all of the
>> interfaces configured. I have also already written a lot of the code that
>> deals with the state transitions. All I am talking about doing is
>> implementing a tiny little finite state machine. It's a pretty trivial
>> programming task. In fact, I think it was covered in my first year at
>> Carnegie Mellon University. Of course, I had already figured out how to
>> write such things in high school, I just did not know what it was called at
>> that point. My point is, that this is not
>> yet-another-cluster-communication-engine. It is a very specific and small
>> finite state machine designed solely with the goal in mind of making FS
>> have just enough information to coordinate call fail over internally. If I
>> recall correctly, a lot of people also said writing yet-another-VoIP-server
>> was a waste of time, but now we have FreeSWITCH, and it was obviously worth
>> the effort. And I am not even trying to do something as complex as that. If
>> you think this is yet-another-cluster-communication-engine, you are missing
>> the point. It is not. It never will be.
>>
>> Look at Sonus, Genband, Broadsoft, Veraz, etc. All the big-name
>> carrier-grade telecom providers have a built-in solution for automatic call
>> fail over. The only way FreeSWITCH will ever compete with such solutions is
>> if it also has that feature. Pacemaker and Corosync are overkill just to
>> get FS to handle single node failures and provide call recovery. It took me
>> a full 3 months of working with them every day to really understand how to
>> deploy them properly in conjunction with FreeSWITCH and Postgres to provide
>> a carrier-grade hot-standby solution which was robust enough to handle 99%
>> of the failures I could throw at it. Granted, this was back when the
>> configuration still needed to be written by hand in XML and prior the
>> existence of any resource agent for FreeSWITCH. But, even with those
>> changes, deploying Pacemaker and Corosync is not a simple task. If that is
>> the requirement for FS to have HA, it will never truly stand a chance
>> against commercial offerings.
>>
>>
>>
>> _________________________________________________________________________
>> Professional FreeSWITCH Consulting Services:
>> consulting at freeswitch.org
>> http://www.freeswitchsolutions.com
>>
>> 
>> 
>>
>> Official FreeSWITCH Sites
>> http://www.freeswitch.org
>> http://wiki.freeswitch.org
>> http://www.cluecon.com
>>
>> FreeSWITCH-users mailing list
>> FreeSWITCH-users at lists.freeswitch.org
>> http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
>> UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users
>> http://www.freeswitch.org
>>
>>
>
> _________________________________________________________________________
> Professional FreeSWITCH Consulting Services:
> consulting at freeswitch.org
> http://www.freeswitchsolutions.com
>
> 
> 
>
> Official FreeSWITCH Sites
> http://www.freeswitch.org
> http://wiki.freeswitch.org
> http://www.cluecon.com
>
> FreeSWITCH-users mailing list
> FreeSWITCH-users at lists.freeswitch.org
> http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
> UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users
> http://www.freeswitch.org
>
>


-- 
Anthony Minessale II

FreeSWITCH http://www.freeswitch.org/
ClueCon http://www.cluecon.com/
Twitter: http://twitter.com/FreeSWITCH_wire

AIM: anthm
MSN:anthony_minessale at hotmail.com
GTALK/JABBER/PAYPAL:anthony.minessale at gmail.com
IRC: irc.freenode.net #freeswitch

FreeSWITCH Developer Conference
sip:888 at conference.freeswitch.org
googletalk:conf+888 at conference.freeswitch.org
pstn:+19193869900
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.freeswitch.org/pipermail/freeswitch-users/attachments/20130211/b5810288/attachment.html