autocluster - Automatic clustering for Erlang nodes

Add this application to your own Erlang programs to enable automatic clustering for new nodes.

configuration

This app can be be included from source with rebar3 by adding it as a dependency:

{deps,[
    {autocluster, {git, "git://github.com/shaneutt/autocluster.git", {branch, "master"}}}
]}.

Once it is added, you can configure it via app.config:

[
    {autocluster, [
        {heartbeat_interval, 5000},
        {ipaddr, {127,0,0,1}},
        {maddr, {224,0,0,1}},
        {port, 62476},
        {socket_opts, [
            binary, inet,
            {active, true},
            {ip, {127,0,0,1}},
            {multicast_ttl, 255},
            {multicast_loop, true},
            {add_membership, {{127,0,0,1}, {224,0,0,1}}}
        ]},
        {logger, {module, function}}
    ]},
    %% other configurations
].

(The entries in the above configuration, except for logger, are the defaults set for each option unless set otherwise)

For the socket_opts option, check the gen_udp documentation (note that active will be forced to "true" as a requirement of the application).

The logger option allows you to define a module and function that logs will be sent to. This function should accept one argument of the following type:

my_logger_function({Status :: atom(), Message :: string()}) -> ok.

usage

Using the above configuration, two or more nodes that can reach eachother via multicast (and the socket_opts provided) will be joined:

• Once a node becomes a member of a cluster, it stops sending out a heartbeat (but listens for the heartbeats of others)

• Once a node receives a heartbeat it will attempt to join that node and log any failures