[ejabberd] Clustering, data (state) sharing, and hooks firing on the cluster / nodes

Hisham Mardam Bey hisham.mardambey at gmail.com
Fri Nov 18 07:42:36 MSK 2011

A quick update on my findings after doing some more spec reading.

Using rosters and presence I can simulate the exact environment and
online / offline notifications that we need for our business logic.
The only rule I still have to meet is blocking all communication by
default (messages) unless 2 members have successfully subscribed to
each others rosters. Any hints?


On Thu, Nov 17, 2011 at 1:06 PM, Hisham Mardam Bey
<hisham.mardambey at gmail.com> wrote:
> Hi folks,
> I'm fairly new to ejabberd and Erlang (3rd day using it as of writing
> this email) and I am having fantastic results with both so far. We
> want to use ejabberd where I work (dating site, we have up to around
> 8K people online wanting to chat). What we have so far is ejabberd
> 2.1.6-2.1 (via apt) coupled with Strophe JS for the web browsers.
> We've written a couple of Erlang modules that update our system via
> presence notifications when people join and leave. We've also got
> another module that coordinates invitations between users and must
> keep some state about who's said "yes" to who's invitation so that
> subsequent chat messages between the 2 users can go through (other
> wise the module's packet filter will drop it). The goal is to then use
> this by adding a hook on fitler_packet and only let through chats that
> have been approved and "registered" in the system.
> My question is really about the last part, how one would go about
> "sharing" such state across the cluster, and how do hooks work in a
> cluster? I am still reading up on Erlang and ejabberd clustering and
> how it works.
> If I have multiple nodes in my cluster with users connected to
> different nodes what is the recommended way of tracking such
> invitation state? Also, if I use presence to figure out when a user
> has left through a hook, will the presence hook fire only on the node
> the user was connected to and left (presence changed)?
> My plan is to read up some more on how Erlang and ejabberd handles
> clustering then come back here and update this question. In the mean
> time, any helpful information or resources explaining how this stuff
> works are greatly appreciated.
> hisham.
> --
> Hisham Mardam-Bey
> http://hisham.cc/

Hisham Mardam-Bey

More information about the ejabberd mailing list