GPL and Nagios agents

[Lukman]

Hi,

Just wondering how does the GPL license applies if we deploy a custom agent to our client sites? Does this count as 'releasing' software under GPL?

We're looking into using Nagios Core as our monitoring system however our network includes client sites that are strictly speaking not 'our' sites. Does anyone else use Nagios in a similar fashion? What are the licensing implications?

Thank you in advance.

[abrist]

See: http://en.wikipedia.org/wiki/GNU_General_Public_License
You are mostly "free" no do what you wish with nagios core. Copyright and license notices can not be changed. Any modifications/additions to the code must be made available.

What do you mean by "custom agent"?

[Lukman]

Say we have provide our clients with software that they run and install at their premises. We then install a Nagios agent at their premises, and then modify that agent to pick up events generated by our software.

Does this count as us 'releasing' a Nagios Core modification? Which would then mean that the source code of the modification must be made available. Whereas if we do not 'release' the modification, the licence do no require us to make it available. From http://www.gnu.org/licenses/old-license ... stedPublic :

Does the GPL require that source code of modified versions be posted to the public?
The GPL does not require you to release your modified version. You are free to make modifications and use them privately, without ever releasing them. This applies to organizations (including companies), too; an organization can make a modified version and use it internally without ever releasing it outside the organization.
But if you release the modified version to the public in some way, the GPL requires you to make the modified source code available to the program's users, under the GPL.

Thus, the GPL gives permission to release the modified program in certain ways, and not in other ways; but the decision of whether to release it is up to you.

[slansing]

I don't believe so, the agent's themselves have their own respective licenses. What modifications would be made to the agent? In many cases you could simply write a plugin to tie that agent to the software you are monitoring and then ship the results up to Nagios. This could be done with a number of the active agents such as NCPA, NRPE, or Nsclient++.