Modbus/TCP??

[Andreas Ericsson]

Andrew Cruse wrote:
> Hugo van der Kooij wrote:
>> On Mon, 27 Aug 2007, Andrew Cruse wrote:
>>
>>> I'm looking to take my monitoring of a transfer switch to the next
>>> level beyond just dry-contacts.   The switch manufacturer offers a
>>> monitoring card that is TCP/IP capable, but it does not expose the
>>> various things it monitors over SNMP, but instead uses ModBus/TCP. 
>>> I've not run into that format before, but I gather it is, or is
>>> rapidly becoming, the standard communication protocol for similar
>>> devices.  Has anyone come up with a Nagios plugin that works with
>>> ModBus/TCP??  Unless I'm just not searching for the right thing,
>>> Google has been of no help at all. 
>> Based on the modbus.org website it seems this is not an open protocol
>> and implementing it might open one up to legal claims. Not being a
>> lawyer makes me a bit cautious. This might impede others as well.
> 
> 
> Well, from their FAQ, they say, "The Modbus protocol was transferred from
> Schneider Electric to Modbus-IDA in April 2004, signaling a commitment to
> openness. The specification is available free of charge for download, and
> there are no subsequent licensing fees required for using Modbus or Modbus
> TCP/IP protocols."  
> 
> I'm poking around now to see if maybe there's some kind of client daemon
> already available out there that I could perhaps use Nagios to pull output
> from.  Whatever I manage to rig up I'll put something up on nagiosexchange
> for any others that might need it.
> 

modbus rings a bell. I *think* I might have written a partial, device-specific
implementation of it once, a long time ago.

AFAIR, it's a fairly simple binary protocol along the tried and tested variant
of head+body.

I'll have a look at work tomorrow and see if I can find it. If so, I can
most likely post it here. It'll require a lot of tweaking though, but it
should be better than starting from scratch.

-- 
Andreas Ericsson                   andreas.ericsson at op5.se
OP5 AB                             www.op5.se
Tel: +46 8-230225                  Fax: +46 8-230231

-------------------------------------------------------------------------
This SF.net email is sponsored by: Splunk Inc.
Still grepping through log files to find problems?  Stop.
Now Search log events and configuration files using AJAX and a browser.
Download your FREE copy of Splunk now >>  http://get.splunk.com/
_______________________________________________
Nagios-users mailing list
Nagios-users at lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/nagios-users
::: Please include Nagios version, plugin version (-v) and OS when reporting any issue. 
::: Messages without supporting info will risk being sent to /dev/null