Doh! Now that I actually have the graphs going, I see that Hobbit is graphing all of the values, which is even better! So now my only question is how to graph Farenheit instead of Celcius....I assume I would have to edit do_temperature.c:

sprintf(rrdvalues, "%d:%d", (int)tstamp, tmpC); dprintf("RRD %s, value %d\n", rrdfn, tmpC);

and change those tmpC to tmpF (And also edit hobbitgraph.cfg and s/Celcius/Farenheight)?

-Charles

Charles Jones wrote:

1. How can I graph Farenheit instead of Celcius?
2. I have two different temperature outputs (different machines), will Hobbit pick up the correct value from both? Here are examples, directly cut and pasted from the hobbit status page...

Machine 1: (I think this is the "usual" temperature output)

Tue Feb 15 11:45:33 MST 2005 Temperature status:

Device Temp(C) Temp(F)

AMBIENT 20 68 CPU0 40 104 CPU1 40 104 CPU2 40 104 CPU3 40 104

Status green: All devices look okay

Machine 2: (This one looks a bit different) Tue Feb 15 11:46:20 MST 2005 Temperature status:

Device Temp(C) Temp(F)

Board 0 34 93 Board 1 35 95 Board 2 35 95 Board 4 34 93 Board 6 37 98 Board CLK 25 77

Status green: All devices look okay

Note that for Machine 2 I believe the Board CLK is the value we want to graph.

To unsubscribe from the hobbit list, send an e-mail to hobbit-unsubscribe at hswn.dk

On Tue, Feb 15, 2005 at 12:07:00PM -0700, Charles Jones wrote:

I noticed when you click a disk graph, that the url indicates which partitions to display via "&first=1&count=4", would show all four disk partitions. If you change that to &first=1&count=1, it only graphs the first disk partition (usually /).

I tried the same thing with the temperature graphs and it worked, ie: http://www.myhobbitserver.com/hobbit-cgi/hobbitgraph.sh?host=somehost.com&se...

Displayed the graph for only "Ambient".

You have sharp eyes - yes, this is precisely how hobbitgraph handles cases where there are multiple graphs combined in one image. It builds a list of the available graphs, sort them by a key - for disks that is the filesystem name, for temperature it's the name of the temperature monitor - and uses the "first" and "count" settings to decide which ones from this set of data to include on the current graph.

I guess a question I would have about that is how could I set that as default, or even better, if there was some GUI way to select which values to include in the graph (maybe its part of Cacti already, I dunno).

There's currently no way of setting up a default view of a graph - apart from which graph to include in the default set, you might also want the monthly graph as the default, instead of the 48-hour graph; or you want the graph to be clipped at some maximum value by default; or ... lots of other possibilities. Plus a GUI to dynamically tune the graph in real-time.

It's something I want to improve after the 4.0 release is out. So I'll happily note your input, but postpone any implementation of it till later. Some of the stuff I want to do requires changes to the RRDtool library - Tobi Oetiker (RRDtool author) doesn't want to do these changes for RRDtool 1.0.x, so I'll probably end up including a modified RRDtool with Hobbit. And that's just too much work for 4.0.

Regards, Henrik

Thanks Henrik, as usual your advice worked like a charm. I also changed the GPRINT statements to use tempf so the legend would be correct.
Final version:

[temperature] FNPATTERN temperature.(.*).rrd TITLE Temperature YAXIS Fahrenheit DEF:p at RRDIDX@=@RRDFN@:temperature:AVERAGE CDEF:tempf at RRDIDX@=9,5,/,p at RRDIDX@,*,32,+ LINE2:tempf at RRDIDX@#@COLOR@:@RRDPARAM@ GPRINT:tempf at RRDIDX@:LAST: \: %5.1lf (cur) GPRINT:tempf at RRDIDX@:MAX: \: %5.1lf (max) GPRINT:tempf at RRDIDX@:MIN: \: %5.1lf (min) GPRINT:tempf at RRDIDX@:AVERAGE: \: %5.1lf (avg)\n

Thanks again! -Charles

Henrik Stoerner wrote:

On Tue, Feb 15, 2005 at 11:49:55AM -0700, Charles Jones wrote:

...

1. How can I graph Farenheit instead of Celcius?

The easiest way of doing that is to change the hobbitgraph.cfg definition for the graph!

In the [temperature] section, there's this line that picks out the "temperature" setting from the RRD file:

DEF:p at RRDIDX@=@RRDFN@:temperature:AVERAGE

This is an RRDtool "DEF" (definition) that defines a variable "p at RRDIDX@" (the "@RRDIDX@" is handled by hobbitgraph, and is needed because there are multiple graphs. So essentially you get p0, p1, p2 etc - one for each temperature*rrd file).

There's also something called a "CDEF" - a Computed DEFinition. Meaning you can do math on the data you have in the RRD. So to compute Fahrenheit, you do the usual F = (9/5)*C + 32 - using Reverse Polish Notation (RPN) which is what CDEF's understand:

CDEF:tempf at RRDIDX@=9,5,/,p at RRDIDX@,*,32,+

Now you have two values: p at RRDIDX which is the original Celsius temperature, and tempf at RRDIDX@ which is the Fahrenheit equivalent. So to get the graph for the Fahrenheit one, change the LINE2 graph definition to use the Fahrenheit value:

LINE2:tempf at RRDIDX@#@COLOR@:@RRDPARAM@

Finally you just change the Y-axis label, and end up with this definition:

[temperature] FNPATTERN temperature.(.*).rrd TITLE Temperature YAXIS Fahrenheit DEF:p at RRDIDX@=@RRDFN@:temperature:AVERAGE CDEF:tempf at RRDIDX@=9,5,/,p at RRDIDX@,*,32,+ LINE2:tempf at RRDIDX@#@COLOR@:@RRDPARAM@ GPRINT:p at RRDIDX@:LAST: \: %5.1lf (cur) GPRINT:p at RRDIDX@:MAX: \: %5.1lf (max) GPRINT:p at RRDIDX@:MIN: \: %5.1lf (min) GPRINT:p at RRDIDX@:AVERAGE: \: %5.1lf (avg)\n

Untested, but you get the idea ... the RRDtool website has some more examples and tutorials on CDEF's.

Regards, Henrik

To unsubscribe from the hobbit list, send an e-mail to hobbit-unsubscribe at hswn.dk