NAME

YATG - Fast SNMP data poller daemon, with storage and graphing

DESCRIPTION

YATG is an application which is intended to be run persistently. At intervals it will wake up and poll network devices for SNMP data, and then store or print that data. In this distribution are also included examples for presenting simple CGI web pages with graphs.

YATG is flexible, efficient and powerful. It can poll a large number of devices with thousands of ports in just a few seconds. The configuration is very simple, and the defaults sane (it's designed for sysadmins, after all).

You can use YATG both for historical logging, such as traffic counters on ports, as well as short-term monitoring which might feed into, say, Nagios. Wherever possible, data is translated to human-friendly formats for storage, such as using Leaf Names instead of OIDs, translated values ("up", "down", etc) and device port names rather than SNMP Interface Indexes.

How Does It Work?

At startup, "yatg_updater" loads its configuration from local files and a database, performs some basic SNMP connections to build a cache about device capabilities and so on, and then goes to sleep.

Periodically, as determined by the configuration, "yatg_updater" wakes up and polls all devices, then stores results, again according to instructions in the configuration.

If you have only the essential dependencies installed (see below) then you can only output results to STDOUT. With other modules, you have more options such as local or remote disk, or memcached based storage.

"yatg_updater" will re-load all its configuration if given a HUP signal. If you run the daemon persistently (for example with "daemontools") then a cron job once a day is a good way to refresh the configuration. There is reference to this in one of the bundled example files.

What's in this distribution

"yatg_updater"

        This is the main application, designed to be run persistently. It
        does not accept any input and only produces output when in debugging
        mode. It is a smart wrapper for the SNMP::Effective module.

YATG::Store family of modules

        These are modules which take the SNMP poll results and store them to
        either local Disk, a Memcached server, or the disk on a remote
        networked server.

YATG::Retrieve family of modules

        These are modules which read stored results back to you, for a given
        time window. The data can be retrieved from local Disk, a Memcached
        server, or the disk on a remote networked server.

RPC::Serialized handlers

        If storing and/or retrieving on a remote networked server, it should
        run an instance of RPC::Serialized, and these are the RPC Handlers
        for that server (see that module's documentation for further
        details).

CGI For the special case of viewing graphs of disk-based poll results

        for switch port traffic counters, there is are two CGI scripts. One
        is a wrapper which presents an HTML page embedded with PNG images
        created from the other script.

Examples

        The "examples/" folder includes a copy of each of the files you
        should need for a complete deployment of YATG. Obviously some of
        them contain dummy data.

Where to go from here

To begin with, you probably want to see how to configure "yatg_updater" in YATG::Config.

Alongside that, there are examples of all the files you should need to install, in the "examples/" folder of this distribution.

LOGGING and TESTING

This module uses "Log::Dispatch::Syslog" for logging, and by default will log timing data to your system's syslog service. More information is provided in the YATG::Config documentation.

To run in debug mode, where timing data is output to standard out rather than syslog, set the environment variable "YATG_DEBUG" to a true value.

To run the poller just once, set the "YATG_SINGLE_RUN" environment variable to a true value. This is great for development. It makes "yatg_updater" load its configuration, generate the device hints cache, sleep and then run just one poll cycle before exiting.

For example:

YATG_DEBUG=1 YATG_SINGLE_RUN=1 /usr/bin/yatg_updater /etc/yatg.yml

DEPENDENCIES

The following modules are dependencies of the YATG system, in addition to the standard contents of the Perl distribution itself:

Class::Data::Inheritable
DBI
Log::Dispatch::Syslog
Module::MultiConf
Net::Netmask
Readonly
Regexp::Common
SNMP
SNMP::Effective (but not version 1.0) Time::HiRes

The following modules are optional, and allow you to use additional bundled features such as data storage, graphing, and so on:

CGI
Cache::Memcached
RPC::Serialized
Tie::File::FixedRecLen
URI::Escape
perlchartdir

SEE ALSO

SNMP::Effective

This system uses SNMP::Effective at its core do the polling.

RPC::Serialized

Store polled data on another server using RPC::Serialized.

AUTHOR

Oliver Gorwits "<oliver.gorwits@oucs.ox.ac.uk>"

COPYRIGHT & LICENSE

Copyright (c) The University of Oxford 2007.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.