OK, here it is again, for your reading pleasure. :-) Cut and pasted from my sent items - you may have to read the original thread to appreciate the context, but the process is sound for any graph The original thread is here http://www.hswn.dk/hobbiton/2010/06/msg00068.html
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Hi
When in doubt, take it from the top.
- Make sure data is coming through. (You have an icon, so it probably is)
- Check that USERS:227 really is on its own line in the html display. (Use view source in your browser) Anything else on that line will cause problems, and your data will not go into the rrd file.
- Check that an appropriate rrd file is being created.
- Check that there is data in the rrd file. rrdtool dump <rrdfile.rrd> | grep name (Should see "<name> USERS </name>")
- Check there is data too. rrdtool dump <rrdfile.rrd> | grep "/row>" | grep -v "NaN" (You should see values between <v> and </v>
If all of the above are good, then you are getting data, and storing it. This means your issue is in the graphing. (See below) If they are failing, check as follows 1a. Make sure your test is running correctly and sending data properly. (troubleshooting guides available in many places) 2a. Modify your data output to ensure the data:value is really on its own line. NOTHING may share the line. Even if it looks alone in the display, it may have HTML formatting stuff before or after. This will cause it to break. 3a. Make sure the appropriate entries exist in hobbitserver.cfg. (looks OK in your case) If in doubt use NCV_testname="*:GAUGE" It's a hack, but valid, and adds anything it thinks is a value to the rrd file. Once you know what the entry looks like in the rrdfile (see step 4 above) you can refine the NCV entry, delete the rrdfile and let it start over. Remember, a restart is required after making changes to hobbitserver.cfg 4a. Make sure the rrd helper apps are running on your server. Check ~/server/etc/hobbitlaunch.cfg to make sure nothing related to rrd is disabled. If in doubt, do a restart. Log files may also help here. 5a. Check the log files. Normally /var/log/xymon/rrd*.log Lots of grep required to make it look sane.
As mentioned, if all of the above is good, then we probably have a graphing problem. Looking at your graph definition, we need to check the following. 6. [graphname] must match the test name as seen on the main page and must be unique. (You are getting empty graphs, so this is probably correct) 7. TITLE and YAXIS is free-form text, they can be anything, but no special characters please. 8. DEF is a vital line, and you need to get it right. DEF:AnyName=rrdfile.rrd: column_name:AVERAGE This is defining an internal "variable" called AnyName to be the value of the column_name in rrdfile.rrd column_name must match the name you get from doing rrdtool dump rrdfile.rrd (Step 4 above) Getting this bit wrong is common. 9. AREA defines the graph type, data and colour. AREA:AnyName#00CC00:Description AREA could be LINE1, LINE2, it merely defines your graph type. (As long as it's valid, it should be good) AnyName has to correspond to the "variable" you defined in the DEF line. (See 8 above) Get it wrong, no graph. #00CC00 is an HTML colour definition See here for a partial list of valid values. http://html-color-codes.com/ Description is what will appear next to the colour legend just below the graph. (It's also free-form, but no special characters) 10. COMMENT is also free-form, but no special characters. (Comment it out for troubleshooting) 11. The GPRINT lines are simply defining your min, max, cur and average values below the graph. For troubleshooting, you can comment them out. (Process of elimination)
Be patient. Because you are using averages, it needs data to average. So it needs at least 2 values. If you have bad timing, it could take as long as 10 minutes to collect 2 values.
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