®
Nagios: A Framework for
Hardware-based Monitoring
October 11, 2007
Kevin Menard
Servprise International, Inc.
kmenard@servprise.com
+1 508.892.3823 x308

Nagios Out-of-the-box
• Only monitors part of network
– Software-based services
– Hardware via SNMP

Structure of Modern Networks

Need for Hardware Plugins
• Necessary for total network coverage
• Monitor non-network services
• Take corrective action with hardware

SNMP isn’t Enough
• Difficult for complex operations
• MIB management can be a hassle
• Security
– Non-existent security until SNMPv3
– May require holes in firewall
• Need hardware-specific plugins

Nagios as Mediator
• Register event handlers with checks
• Execute event handlers due to
checks
• Schedule checks based on event
handlers
• Simple checks, simple event handlers

Hardware-based Plugins
• Handle complex interactions
• Provide semantic meaning
• Provide hardware-specific error messages

Web Service-enabled Hardware
• Standards-defined interface (W3C)
• Supports most modern programming
languages
• Lower cost of client support
• Lower cost for client development

Web Service Security
• Use SSL channel (HTTPS)
• Use HTTP authentication methods
• No special firewall rules needed

Vendor Value Proposition
• Push complex monitoring to 3rd party
• Support widely deployed monitoring
app
• Potential for community contributions

Nagios Value Proposition
• Total network coverage
• Push development off to vendor
• Competitive advantage against other
monitoring applications

What Can Nagios Do?
• Can’t develop plugins for everything
• Register support with vendors
• Perhaps ship packaged up plugins
– Simpler for end users
• Develop an ontology of actions

Example Ontology of Actions

Ontology Benefits
• Common set of checks
• Common set of corrective actions
• Materialized by command definitions
• Vendor interoperability
• Minimized configuration

Ontology Representation
• Use W3C’s OWL standard
• XSL transformation to command
definitions
• Vendors “plug-in” command, keep
command name the same

What Can Vendors Do?
• Embrace open source
• Use open interface
– Can still shield proprietary internals
• Produce open source plugins using
interface

Working with Nagios Community
• Users
– Know what they want to use
– Can offer great suggestions
• Developers
– Know Nagios internals
– Can offer technical support
• Neither are obligated
– Quid pro quo

Plugin Licensing
• Nagios is GPL
• Plugins are not necessarily derived works
• Plugins that do not use GPL code do not
need to be GPL
• Non-open source unlikely to succeed, but
doable

Conclusion
• Lot of value for Nagios, vendors
• Symbiotic relationship between them
• Nagios can technically support vendors, needs
to support them at higher level
• Vendors need to work with Nagios community
• End users win

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Acknowledgements
• Nagios community
• Netways
• Servprise staff
• Special thanks to:
– Melanie Bolduc
– Ethan Galstad