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I'm trying to push disk io statistics from collectl V3.3.5-4 (with the multicast and socket Perl modules installed) through to a Ganglia version 3.0.7 instance.

Configured and followed the instructions here:

but it doesn't appear to work.. it generates the stats to console, but I can't see these in gmond's output... calling via:

collectl -sd --export gexpr,,d=9

Does anybody have any ideas on how to fix this?

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I've also tried this by specifying the multicast address above for collect, but to no avail... – Jon Oct 16 '09 at 19:55
up vote 3 down vote accepted

Someone reported a problem with this some time ago and it turned out there was a bug in the documentation, which I've since fix well over a month ago. If you actually look at the documentation for the ganglia debug setting, you're specifying a 9 and the meaning of that flag are:

1 - print Var, Units and Values
2 - only print sent 'changed' Var/Units/Vales
4 - dump packet
8 - do not open/use socket (typically used with other flags)
16 - print socket open/close info

so that means you're going to have the variables printed on the terminal but they won't be sent over the socket to gmond. Change the 9 to a 1 or even a 17 (to comfirm the socket is being opened) and I think you'll be ok after that.

I also noticed you haven't specified a monitoring interval with -i so that means you'll be sampling once a second interactively or 10 seconds as a daemon. These intervals work great and I think you need to monitor at that frequency to get accurate data (but that's a whole different discussion) but it may be a lot for ganglia to digest if you plan to collect a lot of different data.

One thing you might want to think of is to generate data in parallel in a local file in plottable format by adding the collectl switches -P -f/dirname -ocz. You could then load this data into a spreadsheet, plot it with gnuplot or use colplot, which is a web-based plotting tool that call gnuplot for you. You can get it as part of 'collectl-utils' which can be found at

Be sure to let me know if this doesn't work. The best way would be in the collectl forum on sourceforge or one of the mailing lists as I only stumbled on your posting by accident.


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Just bumped into this and I see it has never been responded to. IS that good or bad? I do know nobody else has reported problems with the interface AND people are definitely using it. -mark

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I didn't get this fixed in the end, instead I wrote a Ruby wrapper script to collect the stats from collectl... – Jon Jul 19 '10 at 18:01

Don't know if anyone is even watching this thread, but if you're going to SC10 this year I'll be there tomorrow. Feel free to stop by the HP booth and leave your name and contact info and perhaps we'll get to talk. I'm also planning on getting together with Bernard Li to discuss this in more detail and he may even be pulling together a BOF to explore this as one of multiple Ganglia topics. -mark

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