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<p class=MsoNormal>Has anyone tried using this yet? The way to do it seems to
be to set the environment variable RRDCACHED_ADDRESS to the same value as the –l
parameter you used to start rrdcached, before running MRTG.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I’ve been testing this as part of my performance
testing, and it seems a little immature. The cached seems not to support such
functions as tune, create, and info; only supporting update.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>When rrdcached is running on a unix socket, MRTG seems to
work and all is fine – I suspect the tune, create and info are done via
the normal channels. If you use a TCP address, though, you get lots of errors
about ‘dummy’. I think this is the RRD functions choking because
they cannot stat the RRD file, or create it.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>There is also an issue that rrdcached rejects absolute paths
for RRD files when submitted via TCP which seems to be in conflict with the way
MRTG works.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Possibly MRTG should be patched to detect rrdcached mode,
and in this case skip the various checks like verifying the MaxBytes (and
tuning), checking for .log files, and so on. You’d still need to have
the rrd files pre-created unless rrdcached can support this in the next version,
though.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>If rrdcached can support create (as well as update) via TCP
sockets then it will open up the possibility to have one server running
rrdcached and the web frontend, and then a cluster of others running MRTG
processes feeding back to the rrdcached, allowing a huge expansion…<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I’m going to have a bit more of a play with this, but
I’d be interested in hearing anyone else’s experience with this.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Steve<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<div class=MsoNormal align=center style='text-align:center'><span lang=EN-US>
<hr size=2 width="100%" align=center>
</span></div>
<p class=MsoNormal><b>Steve Shipway<o:p></o:p></b></p>
<p class=MsoNormal><span style='font-size:10.0pt'>ITS Unix Services Design Lead<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt'>University of Auckland<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt'>Floor 2, 58 Symonds Street<o:p></o:p></span></p>
<p class=MsoNormal><i><span style='font-size:10.0pt'>09 3737599 ext 86487<o:p></o:p></span></i></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:18.0pt;font-family:Webdings;
color:green'>P</span><span lang=EN-GB style='color:blue'> </span><span
lang=EN-GB style='font-size:10.0pt;font-family:"Arial Narrow","sans-serif";
color:green'>Please consider the environment before printing this e-mail</span><span
lang=EN-GB style='color:blue'> </span><span lang=EN-GB style='font-size:7.5pt;
font-family:"Verdana","sans-serif";color:navy'><o:p></o:p></span></p>
<p class=MsoNormal><i><span style='font-size:10.0pt'><o:p> </o:p></span></i></p>
<p class=MsoNormal><o:p> </o:p></p>
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