NAME

Message::Passing::Manual::Cookbook - Common recipies

Aggregating logs

Logging from an application.

You can use Log::Dispatch, or any log system which will output into Log::Dispatch.

    use Log::Dispatch;
    use Log::Dispatch::Message::Passing;
    use Message::Passing::DSL;

    my $log = Log::Dispatch->new;

    $log->add(Log::Dispatch::Message::Passing->new(
        name      => 'myapp_aggregate_log',
        min_level => 'debug',
        output    => log_chain {
            output zmq => (
                class => 'ZeroMQ',
                connect => 'tcp://192.168.0.1:5558',
            );
        },
    ));

    $log->warn($_) for qw/ foo bar baz /;

Aggregating this log

As simple as using the command line interface:

    message-pass --input ZeroMQ --input_options '{"socket_bind":"tcp://192.168.0.1:5558"}' \
        --output File --output_options '{"filename":"/tmp/mylog"}'

And you've now got a multi-host log aggregation system for your application!

Aggregating syslog

Assuming that you've got a regular syslogd setup and working, then you probably want to keep that. Having some of the log files on individual hosts can be very useful. Also, we'd like to avoid the script being a privileged user (which would be needed to get the standard port).

Therefore, we'll run a syslog listener on a high port (5140), and get the regular syslogd to ship messages to it. The listener will then forward from each host to a central aggregate logger (which is setup as above).

On host collector

    message-pass --input Syslog --output ZeroMQ --output_options '{"connect":"tcp://192.168.0.1:5558"}' 

Configuring your syslogd

This should be easy, here's an example of what to add to rsyslogd.conf to get the syslog resent.

    *.* =192.168.0.1:5140

Aggregating everything

If you have hosts with both applications and syslog that you want to aggregate, then you can easily do both at once. This also means that your apps ship logs to a local buffer process rather than directly across the network - which is more resilient to short network outages.

AUTHOR, COPYRIGHT & LICENSE

See Message::Passing.